Natural History Museum Library JOl^ok 3 IVC- -f (c, p. 4,0 if I 3. C. kZ; PHILOSOPHICAL TRANSACTIONS, GIVING SOME ACCOUNT OF THE Prefent Undertakings, Studies, a7id Labours, OF THE INGENIOUS, IN MANY Confiderable Parts of the WORLD. VOL. LVII. PART I. For the Year 1767. LONDON: Printed for L. Davis and C. Reymers, Printers to the Royal Society, againft Gray s-Inn Gate , in Holbourn. mTdcclxviii. )i » <' a/ ! •• jij '(uWlij 'j-^_r,r Q}jj| iu .ifi yji <3XIVJ ii t2L01 3: . -if! t> U L I 2/lQjblptt < biyorft *. ADVERTISEMENT. r ti 'HE Committee appointed by the Royal Society J to direct the publication of the PhiloJ'ophical PranfaSliom, take this opportunity to acquaint the public, that it fully appears, as well from the council- books and journals of the Society, as from repeated declarations, which have been made in feveral for- mer PranfaSHom , that the printing of them was al- ways, from time to time, the tingle a£t of the re- fpedtive Secretaries, till the Forty-feventh Volume. And this information was thought the more neceffary, not only as it has been the common opinion, that they were published by the authority, and under the di- rection, of the Society itfelf ; but alfo, becaufe feveral authors, both at home and abroad, have in their writ- ings called them the PranJaSliom of the Royal Society. Whereas in truth the Society, as a body, never did intereft themfelves any further in their publication, than by occafionally recommending the revival of them to fome of their fecretaries, when, from the par- ticular circumftances of their affairs, the PranfaRtiom had happened for any length of time to be intermitted. And this feems principally to have been done with a view to fatisfy the public, that their ufual meetings were then continued for the improvement of know- ledge, and benefit of mankind, the great ends of their fir ft inflitution by the Royal Charters, and which they have ever fince fteadily purfued. But the Society being of late years greatly inlarged, and their communications more numerous, it was thought advifeable, that a Committee of their Mem- bers fhould be appointed to reconfider the papers read before them, and- feleCt out of them fuch, as they a 2 fhould ADVERTISEMENT. fhould judge mod; proper for publication in the future of Whitton, in Mid- dlefex: Communicated by J. Bevis, M. D. F. R. S. p. 402. XL. Exrabl of a Letter from John Ellis, Efquire , F. R. S. to Dr. Linnaeus, of Upfal, I\ R. S. on the Animal Nature of the Genus of Zoophytes called Cor allin a p. 404. XLI. An Account of the Aclinia Sociata} or clufiered Animal Flowery lately found on the Sea-Coafis of 1 the XL CONTENTS. the new- ceded Jfands : In a Letter from John Ellis’ Ejquire, F. R. S. to the Right Honourable the Ear of Hillfborough, F. R. S. p. 428* XLII. A Letter from Edward Wortley Montagu’ Ejquire , F. R ■ S. to William Watlon, M. Z> F. R. S. containing fome new Obfervations on whaJ is called Pompey’s Pillar, in Egypt. p. 438. XLI1I. Part of a Letter from W. Watfon, M. D . F. R . S. to John Huxham, M. D. F. R. S. at Plymouth, giving fome Account of the late cold Weather. Dated London, 14 th February, 1767. P-443- X'LIV. Defcription of an Electrometer invented by Mr. Lane j with an Account of fome Experiments made by him with it : In a Letter to Benjamin Franklin, LL. D. F. R. S. p* 45 lm XLV. Of the I?7creafe and Mortality of the Inhabi- tants of the Ifland of Madeira : By Dr. Thomas Heberden, F. R. S. p. 461. XLVI. An Account of fome very large Foffil Teeth t found in North America, and defcribed by Peter Collinfon, F. R . S. p. 464- XLVI l . Sequel to the foregoing Acccount of the large Foffil Teeth : By P. Collinfon, F. R. S. p. 468. XLVIII. A Catalogue of the Fifty Plants from Chelfea Garden , prefented to the Royal Society by the wor- jhipful Company of Apothecaries , for the Tear 1766, purfuant to the Direction of Sir Hans Sloane, Bai't . Med. Reg. et Soc. Reg. nuper Prczfes : By William Hudfon, Societatis Regia & clarijfima Societatis Pharmaceut. Lond. Soc. Hort. Chelfean. PrafeClus & PraleClor Botanic . p* 47°* XLIX. An xii CONTENTS. . XLIX. An Account of feme neutral Salts tnade with vegetable Acids , and with the Salt of Amber ; - which flews that vegetable Acids differ from one another ; and that the Salt of A?nber is an Acid of a particular Kind, and not the fame with that of Sea Salt , or of Vitriol , as alledged by many chemical Authors. By Donald Monro, M. D. Phyfician to His Majeftfs Army , and to Saint Georges Hofpital, F. R. S. p. 479. L. Experiments on the Di filiation of Acids , volatile Alcalies , &c. JJeewing how they may be condenfed without Lofs , and how thereby we may avoid dif- agreeable and noxious Fumes : In a Letter from Mr, Peter Woulfe, F. R. S. to John Ellis, Efquire , F.R,S. " P 517. PHILO- £ * * * * 3 PHILOSOPHICAL TRANSACTIONS. ) ..... Receded in 1765. I. A monjlrom human Foetus , havmg neither Head, Hearty Lungsy Sto?nachy Spleen , Pancreas , Liver , swr Kidnies. By Claude, Nicholas Le Cat, M. D. Profejfor and Hemonjlrator Royal in Anato?ny and Sur- gery ; perpetual Secretary to the Aca- demy of Sciences at Rouen, F. R. S. &c. *Tranflated from the French, by Michael Underwood, Surgeon to the Britifh Lying- in Hofpitaly in London. Read December 1 766, 1\ VT F****, a chair- woman, in and Jan vary 1767. the parifh of Caroffli de Dernetal , aged thirty-four years, was brought to-bed, at nine months end, on tuefday the third of January, 1764, of two children, having already had fix, Vol.LVII, B This [ 2 ] This laft labour, in which floe was attended by the widow Mauger , a midwife of the fame town, be- gan with fo conliderable a difcharge of water, that it was judged, not without reafon, that her pregnancy was attended with a dropfy of the uterus. The firfh child was a girl, well formed, who died in the birth, folely from the obflacles which were oc- cafioned, during thecourfe of the labour, by the fe- cond child, or monfter, which I am going to defcribe. All the lower part of this child, from a finger’s breadth above the navel, was likewife a female, to- lerably well formed, except that on her left foot the had but four toes, joined together by a membrane, like the web of a duck’s foot. But all the parts of this foetus, above the navel, compofed a perfect mold, a fhapelefs nrnfs, reprefented in the two following figures, of which it will be neceftary to read the explanation, in order to have a juft idea of the external appearance of this monfter. The drawings are reduced to almoft half the na- tural fize, both as to length and breadth ; from whence it may be obferved, that each of the children, who had lived to their full time, had acquired, in this dropfical womb, a bulk pretty near equal to that of other children, born at full time, when twins, and not very thriving. The full lize of our monfter was twelve inches fix lines, and the navel was in the middle of this fpace. . \ . , ,J i Jf ' S' ft l ! • i,j • ut • : ' T AiB L E '< / PU/VC rt/ /. (P J ftcrrt fU'/l }■; t , \ i 1. It fent, upwards, branches to the mufcles, to the vertebra, and thence to the ribs j for, by blow- ing into the trunk, the air came out at the origin of the uppermoft rib I had differed. 2. Below, it formed two large iliac veins, g. which took the ufual courfe. c. The trunk cut, belonging to the aorta inferior , of the length of a line. f. The diftribution of the reft of this aorta , or right iliac , through that fide of the pelvis. g. The iliac veins going off to right and left, as ufual. .o h. The orifice of the umbilical vein, being fo exadtly of the fame diameter, of the fame white colour and ftrength, and of the fame confidence with the divided trunk, e. that at firft fight, I took this for the fame veffel. The trunk, d. was much thinner, and of a more bluifli tint. Under [ 11 ] Under the umbilical vein, h. was the umbilical ar- tery on each fide, which went as ufual into the pelvis , and there fent off the ordinary ramifications. On the right fide, its anaftomofis with the iliac artery was very difcernible ; but on the left we could not difcover the iliac , a veffel which is pretty confi- derable, even in the foetus, and was fo on the other lide, as feen at letter I. On the left fide, the umbilical artery, at its origin, or its infle&ion, had a kind of web of arteries fubdi- vided, fome of which, doubtlefs, communicated with the aorta , or right iliac ; but neither of thefe branches appeared to be near the fize of the right iliac , nor could we find any thing any-wife like to the trunk, e. which I long fufpedted to be the trunk of the right iliac. What veffels then are thefe trunks, d. e. ? Which of the two is the continuation of the umbilical , h. ? This is a very important point, but not eafily deter- mined. It would not have proved fo, if I had in- jected the umbilical vein, as I generally do in all my monfters ; or if I had taken more care of the parts about the kidney-liver , which I certainly fhould have done, had I but fufpeCted fo many fingularities. I faid, that at firft fight, I took the trunk, e. to belong to the umbilical vein, and it is dill an opinion, to which I am inclined, for the following reafons. 1. At this part, e. the aorta had its greateft cir- cumference; and, in tracing it from this trunk, above as v/ell as below, it grew lefs and lefs. This was, therefore, its trunk, or origin, and could not be a branch of it. C 2 2. I [ 12 ] 2. I have already faid, that the mouths, h. of the umbilical vein, and, e. of the aorta inferior , were exadtly of the fame diameter, of the fame white color, and of the fame ftrength ; and that the other veffel, d. was much weaker, of a laxer texture, and of a fomewhat livid color, like the coats of the veins. 3. The umbilical vein is, with refpedt to the mo- ther, or to the placeiita , which tranfmits the blood to the foetus, a real artery, going from the center to the circumference, or from the principal body, which is the mother, to an adjoining organ, which is the child ; and the umbilical arteries are properly veins, which return the blood from that adjoining body to the common center of the grand circulation. The blood from the umbilical vein then is truly an arterial blood to the foetus. In the ufual ftrudlure of the e?nbryo , nature has fhortened all the ways, to bring the arterial blood of the mother more fpeedily into the heart, into the very aorta mferior of her foetus. Therefore, in a fubjedt, where there is no heart, or even liver, that vein ought to communicate imme- diately with the aorta mferior. In this manner one conceives how this fubjedt could do without a heart, the umbilical blood being a continuation of that from the arteries of the placenta , the uterus , and in Ihort of the mother ; the impulfion of the maternal blood was propagated by that aorta through all its ramifica- tions both above and below. In one word, the heart of the mother fupplied that of the fcetus, and the circulation in this was a continuation of that of the mother. Thefe are the reafons inclining me towards that fir ft opinion ; and here are thofe that fufpendcd my judgment for fome time in favor of the fuppolition [ 13 ] of a communication of the umbilical vein with the trunk, d. of the vena cava of the fcetus. 1. In every foetus the umbilical vein empties itfelf into the vena-cava in the liver; therefore nature hath here followed her ufual courfe. 2. With regard to the arterial trunk, e. it is clofe by the divifion, g. of the Iliac vein, whence it is very likely that it was the left iliac vein which was divided. This laft, and above all ftriking reafon, made me employ almoft a whole morning, in looking over and over this left iliac region, to difcover the divided veffel, which would have put the whole matter out of difpute ; but I could find no trace or appearance of it. All the veflels communicating with the left umbilical vein appeared very intire, though deprived of part of their ramifications by which the air efcaped, but all grew in their courfe lefs and lefs in diameter. Which thenr was the origin of this left umbilical artery ? doutlefs the branches of the trunk, f. of the aorta , which were numberlefs in the pelvis , but had partly been fpoiled the preceeding night, in diffeding the reffium , uterus , and blad- der of this monfter. I add, that this trunk, e. was joined to fome membranes, which we were obliged to pull about, in order to make it turn to the left, and this diredion appeared not to be its natural pofition. Be it granted, for a moment, that, e. is the left iliac, and that the umbilical vein joins it at, d. ; how could the blood circulate in this foetus ? How could it have lived the nine months r d. is evidently a trunk of the cava, which generally enters the right auricle of the heart, dividing, like this, into the 7 cava [ H ] cava fnf.erior, d. b. which rids by the *: vertebrae up to F. and into the cava inferior , d.g. i. It would be abfurd to place the only moving power of circu- lation in the vena- cava, or indeed in any vein. 2. When you have placed it there, what will this fuppofition tend to ? 3. This vein fubdivides, and ramifies itfelf through the kidney-liver , the mufcles and the fpine ; but none of its branches communi- cates with the aorta. The aorta on its part fends feveral branches into the kidney liver , very (lender, and refembling, by their tranfverfal dire&ion, the common emulgents, but very different in (ize. If then the circulating force were placed at d. it could only produce an inverfe circulation, by the communica- tion the cava might have by its capillary branches, with the like ramifications of the aorta, which fup- pofition feems too much againff nature to counterba- lance the other opinion, which makes the trunk e. of the aorta , a portion of the umbilical vein, and the fubftitute of the heart. Another anatomical fadt proves this laft opinion ; which is, that the aorta, and efpecially the fuperior, F. ran up as high as the cranium , and was of a pretty coniiderable (ize, while the venal trunk, d. had nothing but capillary branches in the upper parts j fo that it almoft appeared evident that the veffel, e. F. was connected with the chief mover of the fluids. Wherefore, fuppofing the trunk, d. to be the vena porta , or an imperfect cava going to fome of the vifeera , being the rudiments of an imperfedt heart, or a vena-cava ending in a pouch, as the inteftines did which fhould have entered the ftomach, if there had been one; the difficulty almoft diiappears. I fay almoft, becaufe, even on this fuppofition, if there was a circula- [ *5 ] tion in this monfter ; we muft admit Tome anajhmofes , between the arterial and venal fyftem, which fupplied thofe found in other fcetufes j fince the venal blood muft in fome place or other re-enter the arterial torrent. Such might be the anaftomofis , K. fig. 4. For, by this hypothefis, the vafcular fyftem of this fubjedt would be reprefented by fig. 4. in the following manner. A. The umbilical cord. B. The inteftinal tube. D. The kidney-liver. E. A fort of glandula renalis. a. The umbilical vein ; the great mover of the fluids. b. The aorta , a continuation of that vein. c. d. aorta fuperior , accompanied by the vena- cava. e. Aorta inferior. f. The diftribution of the iliac. g. The umbilical arteries, making a part of the diftribution. h . The trunk of the vence-cavce coming either from the portae, or from the vifcus D, or forming a blind pouch in that part. Some traces of the vena-cava fuperior appear towards C. I. The cava inferior going to form the iliacs. K. A neceflary anaftomofis between the two kinds of veflels, arteries, and veins. I place it ifi this confpicuous fituation, though it might have been any where elfe. I repeat [ 16 ] I repeat it again, if I had but fufpeCted fo many Angularities, what I now can give only by way of conjecture, might have become demonftra- ble in faCt. It is fcarce probable that I fhall ever have fuch another opportunity ; but it is more fo, that it may offer to fome one among the great num- ber of the literati in Europe, who read the Philo- fophical Tran factions. This was the principal mo- tive that determined me to prefent this obfervation, though imperfeCt, to the Royal Society. Why fhould we hefitate to make a publick acknowledge- ment of our faults, when our brethren may profit by, and amend, them ? Another motive, which engaged me to offer this obfervation, fuch as it is, was, that even the im- perfection of it does not affeCt the ufeful confe- quences deducible from it : for, whatfoever may have been the difpofition of the blood-veffels of this monfter, it is a faCt abfolutely certain, that it had no heart, nor any other vifcus in the place of it ; and that the circulation of the fluids, which appears to have taken place from the exiftence of the principal ar- teries and veins, could not have had any other moving power than the circulation of the mother itfelf. Hence this child, moriftrous as it is, demonftrates the cir- culation of the blood from the mother to the foetus, and from the fcetus to the mother again ; which fome moderns deny, and others endeavour, at leaft, to render doubtful. I prefented to the Academy at Rouen fome years ago, feveral obfervations which fa- voured die antient lyflem ; the prefent comes to their fupport, to give this excellent hypothefis of Harvey all the credit it deferves. The [ *7 ]- The child I fpeak of had no mouth, cefophagus , nor ftomach, thus it could not, by that ufual paflage, be nourifhed from ihe waters that furrounded it; it could not abforb from the furrounding fluid where- with to fill its veffels, and fupply its growth. It, therefore, follows that it received both its arterial and alimentary fluids from the mother by the umbi- lical cord, and that it owed every thing to that cir- culation, which fome would attempt to annihilate. In the inteftines of new-born children we find a black excrement, called meconium \ this black pulp can receive its color only from a bile thickened by re- tention, and poured dire&ly from the dudius cho- ledochus into the duodenum. Now this foetus, having no liver, nor gall-bladder. See. could have no meco- nium ; therefore the pulp found in the inteftines was of an afh*colour. This monfter had fo little brain, that that vifeus muft have been of fmall import towards the functions of this animal. And yet all thefe brainlefs feetufes are very lively. Mr. Denis, who, in his twelfth conference, has given an account of one of them, and M. Vaifliere, who fent me one from Toulouze, the laft year, both remark, “ that thefe children “ are remarkably lively in the mother’s belly ; .1 — -.O \!// y’K '''/ K Fig. ,fF7- C C'.. N Fxf.10. yy/ i \ \ c ■e K V [ 3i ] Let the fine of EBFm#, its cofine—z/, the tan- gent of BF=z/3, its cofine —b' , the fine of F Ba=p, its co-line—^/, the fine of zzBA — z, the fine of AB— Z, its cofine = Z, the fine of PAO — and radius = i ; then we fhall have the fine of ABF = the fine of FB^z-J- aBA ■=zp^-p'zi and its cofine — ft — pz: Therefore by trigonometry we final! have in the right angled fpherical triangle ABF, as Rad. (1) : cofine BF (b') :: fine ABF [p-\-p'z : cofine BAF — fine of LAB, or its equal . PAO ; therefore £ = b' x/> -\-p'z — tlie fine of the required inclina- tion of the planes LPH, BOD. In like manner in the fame triangle it will be as rad. (i) : cotan. BF ( j ) : : cofine ABF (p' — pz) : cotan. B A = § ; hence Z = B > and Z == — , which are the fine and cofine of the required arc AB. COROLLARY I. If inftead of a fphere we now fuppofe BEGK re- prefents a prolate fpheroid, whofe axis is CP; the figures of the fedtions LPH, BOD, Sec. inftead of circles, will become ellipfes (by the lemma) ; but it is evident that the inclinations of thofe planes to each other, and likewife the inclination of the right lines AC, BC, or the angle ACB, will remain un- altered. COROLLARY II. If BEGK reprefents any primary planet revolving about the fun in an orbit whofe plane co-incides with [ 3* ] with the plane BCD, it is manifefi: that BCD will be its ecliptic, making the angle of obliquity B1E with its equator EAK (whofe pole is P) ; and if B be the place of the fun in this ecliptic, at any given time, the arc BI will be the diftance of the fun from the neareft equinoctial point I ; and the arc BF his declination at the fame time. COROLLARY III. If the plane POG, which pafles through P, the pole of the fpheroid, be perpendicular to the plane LPH, it will alfo be perpendicular to any other plane BOD, which palfes through A, the interfedtion of the equatorial plane EAR, with the plane LPH j there- fore the angle ACO being a right angle, it is evi- dent that AC will be the femi-tranfverfe, and CO the femi- conjugate axis of the elliptic fedtion BOD. * COROLLARY IV. Hence it appears, that the tranfverfe axis of any elliptic fedtion BOD, made by a plane palling through the center of the fpheroid, will always be equal to the equatorial diameter of the fpheroid, but the con- jugate axis will be longer or fhorter, according as the inclination of the planes LPH, BOD, is more or lefs. PROPOSITION II. Fig. 2. To find the length of the femi-conjugate axis CO, of the elliptic fedtion AO b, formed by a plane cutting the given prolate fpheroid POG through its center C, and making the angle PCO with the axis CP. Let [ 33 ] Let the fine of the angle P C O == C G = r, CPrrt.COrrK, (radius being unity) ; draw P O perpendicular to CP : then in the right angled plane triangle B C O, we have as rad. (i) : CO (») :: fine PCO (J) ; BO ( *£) ; and rad. ( i ) : CO («) : : cofine PCO (vG — £x) : BC (W i — f*) ; but from C * the nature of the ellipfis we have -j x — xx f 1 — BCf = jc1 — k £*-, therefore x = - r or putting t — cx — f\ x=^£-r„ and f z r—p ( and f — x ~ whence we fhall have r — d V = W— ^xzv+zv) : Now by proportion I. we fhall find £ == b' x p -f p'z* P —p* Z = / and Z = / t by prop. II. /2 X I 024?'— H ** ^ r__7~p> and = "T* TJ ia%byprop.IV. V = - — and V = yA — q v P q r ~~3 which values bein^ qA—q'v 0 fubfiituted in the above equation will exhibit the nature of the required curve rtRN, in terms of z and v. SCHOLIUM. If the fphere LIKQI reprefents the fun, and the fpheroid BPOD one of the primary planets, it will appear, from the preceding reafoning, that the figure of the fe&ion of its fhadow received upon a plane, which is perpendicular to its axis, will not be a circle (except when the axis of the planet produced pafle.s through the fun’s center) but a curve of the oval kind, whofe fpecies will be known from the foregoing equation. If the fphere LIKQI had been regarded as a fpheroid in the above folution, it is eafy to lee that tlie foregoing procefs would have determined the nature . [ 37 1 nature of the required curve; but the figure of the fun is fo nearly fpherical, that it was not thought necefiary to embarrafs the folution with that confi- deration. Hence the duration of an eclipfe of a given fa- telles may be determined in the following manner : Let BRC (fig. 6.) be the fedtion of the fhadow, through which the fatelles paffes, N/>N the path of the fatelles, making the given angle N p M, with the circle of latitude Ry> M ; BMC a part of the primary’s orbit produced, and M p the given latitude of the fatelles at the time of the fyzygia ; the circle of latitude R/>M is reprefented in fig. i. by the primitive circle B EGD, and the angle R iVL N, by the fpherF cal angle E B A ; therefore the fine of R M N = the fine of E B A = the fine of E B F F B a -f- a B A = apr -f- a' p -\- a' p' — ap x z, and its cofine a= a'p' —ap — apr + a'pX.Z', which for the fake of brevity may be exprefifed by y, and y' ; then putting M/> — n, M N = u, the fine of Mp N = m, its co- fine = m\ and radius = i ; we lhall have the fine of M N P exprefi: by my' -f- m'y ; and therefore we fhall have in the plane triangle M/>N, as the fin.MN/? {rn y -j -my) : M p (yi) : : fine My> N (/;/) : M N ( v ) ; hence v — _j ; from which,, and the equation. of the curve (determined above) ~ ™ p N, and con- fequently, the duration of the eclipfe will become- known. In prop. I. the fine of the angle ABF is expreficd by p - \~p'z} and its cofine by p' —p z, inftead of their true, values pz' -\-p'z> and p'z' — pz ; this was done. r 38 1 to render the following conclufions more fimple than they otherwife would have been ; and as the angle a B A is, by hypothefis, but final], its cofine will ap- proach fo near to the radius, as not to occafion any fenfible error in the refult; and the fame may be ob- ferved with regard to what is advanced in prop. IVr. It remains now to apply, what has been inveftigated above, to the eclipfes of Jupiter’s fatellites, and to examine whether the prolatenefs of his figure will have any fenfible effed upon their durations j and this is become the more neceffary, as that celebrated aftro- nomer M. de la Lande (who candidly acknowledges, that he was excited to turn his thoughts upon this fubjed, from a curfory view of this paper, which was (hewn him by Dr. Bevis*) does not feem to have confidered the quefiion, with that degree of at- tention which I think it demands. But before this can be done with exadnefs, it w:ll be neceffary to have the inclination of Jupiter’s axis, with refped to his ecliptic, and the place of his equi- noxes determined by obfervation, neither of which I believe has yet been done with any degree of cer- tainty ; I fhall, therefore, proceed in this inquiry upon M. de la Lande’s hypothefis, that Jupiter’s axis is per- pendicular to his orbit j and perhaps this fuppofuion is not fo far diffant from the truth, as to occafion any material error in the conclufion. It may alfo be re- marked, that in the general equation given above, > V and V exprefs the fine and cofine of the ferni- L angle of the cone of Jupiter’s fhadow, but this angle can never exceed 3', and confequently we may very * Viet. ConnoilT. dcs Mouy. Celefb 1765, p. 177. fafely [ 39 ] . fafely ufe the radius inflead of V wherever it occurs. By this means the general equation will become ' / r—d V = or which is the fame 7' — dV~xy therefore V— but by prop. IV. V — * f jA — q'v ? which, becaule q is nearly equal to V, and q'u very / fmall with refpedt to q A, will become V — ■„ therefore , from which we {hall find d A v = anc^ ^is equation is exadly the fame with that which would arife from confidering the fun as a circular, and Jupiter as an elliptic plane, limited by one of bis meridians, and always parallel to the di Ik of the fun 5 which fuppolition, the im- menfe diftance of Jupiter from the fun renders very allowable. From this equation an eafy mechanical method, may be derived of delineating the curve of the fha- dow, at any given didance from Jupiter, for as y. de- notes any femi-diameter of the elliptic fedtion of Ju- piter’s body, it is manifed:, that the term y X will exprefs the correfponding femi-diameter of a fimilar ellipfis, whofe axes are to thofe of Jupiter in the given ratio of A to d9. and the term -y is wholly given: Therefore i {arm (fig. 7.) be Inch an ellipfis, and there be drawn through its center M any . number of femi-diameters Mr/, M Me, &c. meeting the el- lipfis r 40 ] Jiplis in a , b> c, Sec. let a A, ^B, cC, Sec. be taken each equal to the given term — , and the points A,B,C, See. will be in the required curve. It appears from confidering the nature of this curve, that it will have two cufps, one at each ex- tremity of its Idler axis, which will approach to- ward each other, according as the diflance J is aug- mented ; therefore, if the diftance of the fedtion of the fhadow, from Jupiter’s center, was taken, fuch that b — the leffer axis of the curve would r — c then vanilla, and the cufps meet in the center, and thereby form two diflindt fhadows (as reprefented in fig. 8) ; in confequence of which, if a fatelles, revolved at that diflance, it might fuffer a double eclipfe, at the fame conjundtion, which remarkable phenomenon may alfo happen, at a lefs diflance from Jupiter, in fome circumflances. I fhall now flaew how the duration .of an eclipfe of a given fatelles may be determined independant of the equation of the curve ; and this, perhaps, will be the more acceptable, as it will afford a prac- tical rule, which may be applied, in every pofition of Jupiter’s axis, with very little trouble. This may be done by the help of the following propofition. PROPOSITION VI. If a circle eD/G be deferibed about the conjugate axis GD, of a given ellipfis A DBG, and a right line E F be drawn, making the given angle Fn D, with [4i] with the conjugate axis, and palling through the given point tt taken therein, it is propofed to deter- mine the length of the fegments F f> E ey intercepted between the circumference of the circle, and the pe- rimeter of the ellipfis. From the point F, draw the right line F d parallel to the tranfverfe axis A B, meeting the conjugate GD in the point dy and the circle in c; draw the lines C F, CJ] Cr, and let ctc be joined : Then by conics we fhall have, as CB:CD tang. F tt D : tang. c 7rD, and in the right lined triangle Ctj-c, it will be as C c (CD) ! fin. Ctt c : : C n : fin. C ctt, whence the angle cCk becomes known ; but as CD : CB :: tang, c C : tang. FC?r j therefore FCjr is known ; from which taking away the given angley'C tt, there remains the angle FCf-, confequently all the angles, in the right lined triangle/C F, together with the fide C/(CD), are known: we (hall therefore have, in the right lined triangle, F J C, as fin. / F C:Cf:: fin. f CF :jfF, one of the required fegments, and by a fimilar operation, the other fegment E e will be found, whence as ef is given, E F will become known. COROLLARY I. The required fegments Ffy E ey will be found in the fame manner, when the given point tt is not taken in one of the axes, but any where between ; but in that cafe, the point where the line EF interfeds the conjugate axis, muft be firfi: determined. COROLLARY II. , If a perpendicular C n be let fall from C upon the line EF, the angle vCn will be given, to which, Vol. LV1I. G . adding I [ 42 ] 4 adding FC?r (found above) the angle FCtf will be known ; hence we fhall have the following analogy for determining En : As tang./ C» tang. FC n :: f n : F /?. Now let K/£H (fig. 10.) reprefent the difk of the fun, and eD fG that of Jupiter, confidered as a circle, whofe diameter is equal to his axis DG, draw N pny the path of the fatelles, making the given angle N/>R, with a right light Rg drawn parallel to the diameter D G, and let ab be the duration of the eclipfe, and V the apex of the fhadow in this hypo- thecs; join V a, V b, and let the plane aV b be pro- duced, till it meets the fun’s difk in K and k , it will then interfed the diik of Jupiter in the line /tt?, and the lines VK, Vb, will alfo touch the circumference of the circle eD /G, in the points e and /, draw the line SV, and it will be the axis of the fhadow, and confequently will pafs through C and M, the centers of Jupiter, and the fedion of the fhadow ; join a M, £M,/’C, e C, and the triangles abViy efD, will be fimilar to each other, and, therefore, ab M being wholly given, jeQ will likewife be known. Let ADBG be the elliptic fedion of Jupiter’s body, and produce e n f both ways, till it meets the periphery of the ellipfis in the points E and F, draw KF, k E, and produce them till they meet with aby produced both ways in N and n, then will N n be the required duration of the eciipFe in the true fhadow : Now the triangles K/ F, K^N, being fimilar, as are alfo the triangles ke E, k b /z, and the fegments F f eE, being given by the preceding propofition, the re- quired legments N'tf, bny will alfo become known, lor they will be to the former fegments in the given ratio of S M to SC. It C 43 ] It may be obferved, that this method is equally applicable, whether the axis of Jupiter is perpendi- cular to his orbit, or not ; for if it is not, we can eafily find by propofition I and II. the fpecies and pofition of that elliptic fedtion of Jupiter’s body, to which a right line conne&ing the centers of the fun and Jupiter is perpendicular ; and this being obtained every thing elfe will remain as before. As it would require more time, than I have to fpare at prefent, to enter into a particular inquiry concerning the alterations, which this irregularity in the fhadow will occafion, in the prefent theory of Jupiter’s fatel- lites, I (hall conclude with obferving, that the errors in the femi-durations of their ecliples, arifing from this caufe, may fometimes amount to 20// in the firft; 50" in the fecond ; 1' 19" in the third ; and n7 14" in the fourth; which errors will, I believe, be deemed fufficiently large to merit the attention of aftronomers. G. Witchell. IV. An [ 4+ 3 Received September 24, 1766. IV. An Attempt to account fo r the uni- verfal Deluge , by Edward King, Efq\ of Lincoln’s-Inn, F. R . S. t.f ■ * * - 1 Read Jan. 22. FTER fo many conjectures as ,767’ have ^een already formed con- cerning the caufe of the univerfal deluge, it may perhaps appear both impertinent to attempt a new folution, and alfo ufelefs, as theories formed on mere hypothecs are always uncertain, and little to be depended upon. But if we give them no more weight than they deferve, and, ceniidering them only as fmall Steps towards the investigation of truth, do not defire any further affent to our conclufions than the proba- bility on which they are founded demands, even fuch kind of enquiries may be of Service, and open a door to new difcoveries. Where we cannot arrive at demonftration we mull be content with probability. Our defpair of attaining the one ought not to make us negleCt the other. And with regard to this remarkable event, the univerfal deluge, every degree of probability, even the fmalleft, that appears in an attempt to account for it philosophically, has its ufe* as it tends to remove thofe objections that are made to the truth of the SaCt, by perfons who may not think the mere relation of it in the Mofaic writings a Sufficient proof of the reality of it 4 or who may be led, from the difficulty there appears [ 45 ] appears in accounting for fuch an event, to doubt of the authority of thofe facred books. Many ingenious hypothefes have been already formed on this fubjedt ; but they all feem liable to moffc infuperable objections : and therefore I make no lcruple to venture another into the world, which appears to me free from fuch difficulties as they are involved in, and more fimple. I am willing, how- ever, it ffiould fall to the ground, as foon as there appear any reafonable and weighty objections to it. I only with that the hints contained in this paper may be a means of leading fome perfon of greater abilities to a more perfedt difcovery ; and that it may always be remembered, that the foffil fhells found in ail parts of the earth, are a fufficient proof of the truth of its having been at fome time or other entirely covered with water, however fallible any attempt to account for the deluge may be. Dr. Burnet, in his theory, has given fuch an account of the deluge, as Dr. Keill has ffiown to be very improbable, and unphilofophical. He has firft de- fcribed the primseval earth fo as to diveft it of all beauty and elegance, and then has afcribed the deluge to fuch caufes, as are not only fomewhat inconfiftent with that part of his theory, where he fuppofes the earth to be well watered and moiftened with dew ; but are alfo inefficient to account for the waters flowing over the tops of the mountains : fince on the breaking of his imaginary (hell, it is impoffible to fuppofe that the waters of the abyfs, even on fuch a concuffion, ffiould flow up high enough upon thofe parts that were left elevated, fo as to cover the moun- tains that now fubfift. Mr. [ 4-6 ] Mr. Whidon has called in the affidance of another planetary body; and hasfuppofed the tail of a comet to be fo greatly condenfed as to afford a quantity of water fufficient for this purpofe. But, befides the inconfidency of this theory with that of gravitation, it is no lefs difficult, according to his hypothefis, to get rid of the water with which the earth was covered, than it is, according to others, to find a fufficient quantity. Mr. Ray has accounted for this amazing event, by fuppofing a change to have happened in the center of gravity of the earth. But how to find a caufe for fuch a change in the center of gravity, and for a reff oration of it to the fame place again, is more difficult, and the fuppofition of it more inconfiffent with our philofo- phical ideas, than any other hypothefis whatever. Such have been fome of the principal theories hitherto advanced, and far be it from me to prefume that mine may not in the end be found equally fallible; but it appears tome at prefent to be more plain and confident, and at the fame time is free from that great difficulty which has perplexed all the red, and is indeed the mod important difficulty in the enquiry, that is, the accounting for a fufficient quantity of water. We find in the Mofaic hidory of the creation, that God at the fird created fea as well as land; and therefore have grounds to believe both from thence, and from the reafon of things, that there was as great a quantity of fea on the antediluvian earth, as there is now upon the earth in its prefent date. We find alfo the whole furface of the earth to be undermined by fubterraneous lines, which make their appearance [ 47 ] appearance in various places, in very formidable vol- canoes. This has been the cafe in Italy, and amongft the Azores, in Tartary, in Kamtfchatca, in South America, in Ireland, in the illands of the Eaft Indies, and in other parts : and we have reafon to believe that thefe fubterraneous fires have made eruptions, not unfrequently, even in the bottom of the lea; as Mr. Mitchell has made appear in his excellent paper con- cerning the caufes of earthquakes*. We have alfo, in the Philofophical Tranfactions, an account of entire illands being railed in the Archi- pelago, and likewife amongft the Azores, . by fuch fubterraneous fires ■j'* ; and Mr. Ray, in his tiavels, mentions a mountain one hundred feet high, raifed by the earthquake in 1538, which alio threw up^fo much earth, ftones, and afhes, as quite filled up the Lacus Lucrinus J. To which may be added, that fofiil fhelis and other marine bodies are fo univerfally found in all parts of the prefent continents and illands, as to amount almoll to a demonftration, that all the now dry land was once covered with fea, and that for a confideiablc fpace of time, probably much longer than the conti- nuance of the deluge is related to have been. For though fuch a violent flux of waters might have thrown up fome Ihells and marine bodies upon the hills and mountains, yet it could not have flung up fuch vaft quantities, nor fo univerfally. The prodi- gious beds of Ihells which we now find in all parts * Philof. Tranf. Vol. LI. part II. p. 566. t Philof. Tranf. No 372, or Eamcs’s Abr. vol. VI. part 11. p. 203, and Jones’s Abr. vol. V. part II. p. 1969 * X Ray’s Travels, old edition, p. 273. cannot C 48 ] cannot well be accounted for, but by fuppofing the waters, in which thofe fhell-fifh lived, to have covered the countries where they are now found, for a long time, and even for ages. The fuppofition therefore, which I am about to advance, founded on thefe fads, is this j that origi- nally Almighty God created this earth with fea and land nearly in the fame proportion as they now remain, and that it continued in that ftate for many ages, during which the bottom of the fea became covered with fhells, and various heterogeneous bodies ; that from the firffc of its creation there were alfo many fubterraneous fires found within the bowels of the earth ; and that, at the appointed time, thefe fires burfting forth at once with great violence, under the fea *, raifed up the bottom of the ocean, fo as to pour out the waters over the face of what was before dry land, which by that means became fea, and has perhaps continued fo ever fince, as that which was before the flood the bottom of the fea, probably from that time has continued to be continent and dry land -f*. * Mr. Mitchell has ftiewn, in his paper on the caufes of earthquakes, that fuch fubterraneous fires are at all times very liable to make eruptions under the fea, and that when they do fo, the earthquakes confequent upon fuch eruptions are more exten- five than any whatever. f I do not mean by this to infinuate that all that part of the globe which is now fea was dry land before the flood : or that the antediluvian ocean was merely of the extent of our prefent conti- nent. I apprehend, on the contrary, that there was always a greater proportion of water on the face of the earth than of continent; and I would only be underftood to mean, that all that which was dry land before the flood is now buried under the fea, whilft that which was a part of the bottom of the antediluvian This I C 49 ] This hypothecs may perhaps be liable to great ob- jections ; but it is at leah confident with what Mofes relates of the fountains of the great deep being broken up j and, without any perplexity or difficulty, accounts at once for a fufficient quantity of water to cover the tops of the higheft antediluvian mountains, even fuppofing they were left handing: though it is not improbable but that they might be thrown down by means of the fame earthquake. If they were lei t handing, fome of them might (on the retreat of the waters from their tops after the hrh concuffion) form, fome of the illands that now fubfih. I muh alfo add, that this hypothecs is perfeClly confident with, and perhaps in fome meafure accounts for, that lingular polition of the hrata of coals, ores, and various kinds of earths (mentioned in Mr. Mitchell’s papei ), which are found always hoping Irony mountainous countries, and higher grounds,, towards the bottom of the lea; fo that what is neared the furface ot the earth in mountains and high countries lies deepeh in low lands and under the fea-.. It is, befides, fomewhat confirmed by that lingular obfervation of Dr. Hafielquih’s, in his travels, (p. 33) where, fpeaking of Natolia and the eahern countries in general, he fays, “ In no place was it more “ evident that the continent, we call earth, was in another may perhaps arife, from this circumdance, that £hells are found in various parts of the earth, which are evidently not the fhells peculiar to the feas adjoining, but fuch as belong to a different climate. This faCt at fird certainly feems to contradict what I have advanced : and yet, when well confidered, it will perhaps rather be found to confirm my hypotheds. For let any one but look on a terredrial globe, and he will indantly fee, that the prefent continents are evidently not in the fame climates as the prefent feas ; and therefore, though the fhells found in many places of the earth are not found in the neighbouring parts of the ocean ; yet, when thofe parts of the earth were ocean, they might have had a very proper climate and fituation there. Thus, for indance, we may obferve that the Mediterranean is in a more fouthern climate than the neighbouring continent of Europe, and in a more northern climate than that of Africa. And the whole C 55 ] whole continent of Afia is in a climate much more northern, than the neighbouring Indian ocean. But, if this folution of the difficulty is not thought fufficient, it may be added, that fo great a con- cuffion, and fuch a change in the figure of the earth, as muft have happened from the fubterraneous fires elevating fo many parts higher than they were be- fore, might poffibly affett the gravitation of the parts of the globe of the earth, and caufe it to re- volve round a different axis after the flood 5 whence there would undoubtedly arife a change of climate in all parts, fufficient to account for the prefent fitu- ation of ffiells, in places fo foreign to the climates where fhell fiffi of the fame fpecies are now found. And as I have before obferved with regard to feeds, fo it may alfo be obferved with regard to fhell fiffi, that the conveyance of a very few of each fort (by the flux of water) to the beds proper for them, would be fufficient to preferve all the various kinds, and to caufe them now to be found in fuch numbers, in thofe parts of the ocean that are beft adapted to each peculiar clafs. Another thing proper to be taken notice of, is the horns and bones of terreftrial animals being found in the earth, together with foffil ffiells j which feems to contradict the fuppofition of the prefent conti- nents having been originally the bottom of the fea. But with regard to this, I muff beg leave to obferve, that probably fome of thofe bones have been depo- fited there fince the flood, and have been covered by an addition of earth, as has happened alfo to fome of the trees and woods that were cut down in this iftand by the Romans. And, as to the reft, it cannot [ 5& ] be fuppofed, but that on the firft great eruption, which poured the waters of the ocean upon the dry- land, there mud have been a violent agitation for fome time, by their flowing backward and forward ; during which interval, the bodies of many terreftrial animals (floating on the water) would be walked to different parts of the new-raifed continent, and be left there as the water fublided. Some little objection perhaps may arife, from its being obferved, that the fea at prefent covers a much greater part of the globe than the dry land does. But I apprehend this was alfo the cafe before the flood; and it may eafily be conceived, that fome part of the bottom of the antediluvian ocean might be flung in the manner fuppofed in this paper, and not the whole ; and that the bottom of the prefent ocean confifts not only of what was before the flood dry land, but alfo of fome part of what was, even from the beginning, the bottom of the fea. I will therefore only juft add, that probably the fame fubterraneous fires (which originally railed the continents and iflands that now appear, and have ever lince been making great changes in the bowels of the earth, and producing thofe tremendous earth- quakes, which have happened from time to time) may in the end break forth with redoubled violence, and deftroy it, in the manner foretold in Scripture. It may not be amifs to add, in confirmation of the foregoing hypothecs, that the beds of fhells, difco- vered in chalk pits, gravel pits, and other places, confid generally of one or two, or at mod: of a very few C 57 ] few different forts in each particular place, as they would of courfe do upon a fuppofition that thofe re- fpeCtive beds were formerly at the bottom of the fea, in the feveral places where thofe different kind of (hell fifh lived and bred ; and that they were from thence* together with the bottom of the antediluvian ocean, raifed up by the force of fubterranean fires : for we may obferve in the prefent feas, that one fpecies of fhell fifh take up their habitation in one place, whiift thofe of a different fpecies are found in fome other ; and that numbers of the fame kind, as for inftance cockles, or oyfters, are generally found on the fame banks. The prefent appearance of fofiil (hells, there- fore, does at lead: in this refpeCt feem confident with the conjectures here advanced : whereas, upon a fup- pofition that thefe foflil (hells were carried to their re- fpeCtive places, at the time of the .flood, merely by the torrent of water that then flowed to and fro, they ought rather to be found mixed promifcuoufly together ; and not thofe of one fpecies in one place ; and thofe of a different fpecies in another,. And I beg leave here to mention* that, fince the writing of the foregoing paper, 1 find an hypothefis fomewhat fimilar to what is here advanced was adopted by Lazzaro Moro, a Venetian author, who aflerts that the continents wCre originally raifed by fubterranean fires ; but he confiders this merely as the caufe of their firfl: and original formation, and not as having occafioned the deluge, nor as having happened at that time. Vol. LVII. I V. An [ 5» 3 Received September 24, 1766- V. An Attempt to account for the formation1 of Spars and Cry ft als. By Edward King, Efq uire , of Lincoln’s Inn, F. R. S. ♦ Read Jan. 29, y N aR 0ur enauiries concerning the- 1767 ’’ works of the Supreme Being, and in our endeavours to inveftigate the fecondary caufes by which the various phenomena o-f nature are ef- fected, we certainly cannot be too cautious and cir- cumfpeCt. Our comprehenlion of things is at beft very imperfeCt j and we may eafily be led, by too hafty a view, to draw falfe' coricluflbns. It there- fore becomes us to be very mod-eft, and to endeavour to go upon fure grounds, before we indulge-any hy- pothecs whatever. But if we obferve this rule, we cannot carry our fearches or conjectures too far, flnee the refult of them will often be the difeovery of what may be ufeful to mankind, and will almoft al- ways increafe our knowledge in fome degree, and be a means of railing in our minds more noble and ex- alted ideas of the Almighty Creator of all things. This confideration encourages me to fling together the following conjectures, with regard to the pro- duction of thofe beautiful and tranfparent fubftances, which go by the name of fpars, cryftals, and jewels ; but I would not venture to confider them as amount- ing to any thing more than queries. I was [ 59 ] I was firft led to entertain thefe thoughts, byob- ferving the nature of Briftol dones, and the various dates in which they appear j and was encouraged to think they might have fome little weight, by ob- ferving alfo the nature- of fpars, and of thofe flony concretions found in large caverns. I (hall, there- fore, firft mention the obfervations I made, 'and then draw my conclufibns. 1. And lii the , finT place, it is known, that 'the Briftol flones grow, within the hollow cavity of fome other rough rfone| and that the fubdance of the external done is porous, and frequently fo 1 drongly impregnated with crystalline corpufcles, that they glitter amongd die earth}; particles, when held up to the light: • 2. In the next place, it is to be obferved, that, wherever there is a.' hollow cavity in thefe kind of dones, the infide is almod always lined with fuch fhining fubdances, • either in a perfect or imperfeft: date. . . 3 . We find the Br idol dones appear in feveral dif- ferent dates: i for in fome places of the cavity, where the crydaljization is not completed, they are of- a dufky red, without any tranfparency ; in others they appear of a dirty yellow j and in others white ; and .-at lad tfanfparent. '4. As to the ' fpars and cry dais formed even in -dints, and other- hard bodies 5 I think they are gene- , rally obferved in fuch as have evidently been at one time or other in a 'loft date, and lay in or near mold places drongly, impregnated with Inline paiticies o- fdme kind or other. ; or elfe they, are found in bodies wherein fome falirie and mold fubdances 'have foi- ■ I 2 merly [ 60 ] merly been inclofed, and prevented from evaporating ; of which kind are the fpars found in foflil fhells, wherein the bodies of the fhell fifh have perhaps lain and perifhed. 5. We obferve, not only in the fmall cavi- ties of fames, but alfo in large caverns, fuch as thofe in the Peak in Derby (hire, Okeyhole in So- merfetlhire, and the famous grotto in the Greek ifland of Andparos, and in fhort wherever moifture defcends through the earth to a void fpace, and flops upon the inward furface, that it there forms cryftals, or fpars, or ftony concretions of fome fort or other ; of which fome are fo very imperfedt, as to have only the appearance of rude heaps of petrified matter, with- out any regular form, which chiefly happens where there is much moifture, and where it defcends, or foaks through pores fo large as to carry many earthy particles with it. 6. To all which I muft add, that Sirlfaac Newton has made it appear, that the tranfparency of bodies is occafioned by the minutenefs of their pores, and the opacity of them by the largenefs of the pores, in which the rays of light being reflected from fide to fide are loft, and prevented from pafling through ; whence it is, that paper becomes tranfparent by being oiled, and the oculus mundi ftone by being foaked in water. Thefe are the principal obfervations on which I found my conjedtures ; and from hence I am induced to conclude, that all thefe above-mentioned fubftances, are formed by means of thofe cryftalline (perhaps faline) corpufcles with which the furrounding earth or porous ftones abound, and which probably are diffiifed C 61 ] ' diffufed throughout the whole globe, and mixed in fome degree with moft ftratas. Thefe fmall particles, I apprehend, are carried along gradually, by the moifture, or vapors, which foak through the pores, till they come to Tome cavity, and there, being flopped by the difcontinuance of the earthy or ftony fubflance from proceeding any further, they collect together in drops, and as they dry and harden, do of coui fe, by their mutual attraction, form themfelves into cryftal- line figures ; and as the pores are more and more filled up, by the acceffion of more corpufcles, or by their mutual attradion which draws them clofer together, they become more and more tranfparent. Some, however, of the bodies thus formed never have any tranfparency at all, being mixed with too many earthy or ftony particles, or other heterogeneous matter, and have fometimes fo much of that as not to be able to put on any regular form, but only to petrify ^ in a confufed heap ; the earthy or ftony particles pre- venting the cryftalline or faline particles fiom forming themfelves, by their mutual attraction, into regular figures j and there being perhaps but few of the true cryftalline corpufcles mixed with them. This feems to be the cafe with many of the ftony concretions in large caverns : and perhaps, from a fmall mixture of thefe fame heterogeneous particles it is, that fpars are inferior to cryftals, and alfo differ from one another. Mr. Platt, in the Philofophical Tranfadions, Vol.LIV. p. 41. has obferved, that fpar feems to be nothing but cryftal debafed by a calcareous earth. I cannot help fufpeding, that what I have called cryftalline corpufcles are in reality a kind of falts ; I will beg leave, therefore, to call them hereafter by D that [ *2 ] that name ; and -will juft endeavour to illuftrate what* I have faid more particularly by theinftance of Briftol ftones. In their firft ftate, thefe are of a dirty red, or fome other dufky color ; but afterwards, as more falts, or cryftalline corpufcles, are added, by the defcent of moifture, or the palTage of more vapor, they begin to be more compact ; and then, the pores becoming fmailer, they approach nearer to transparency, and put on a yellow or whitifh color; and at la ft, receiving a further addition of frits, and having the com- ponent particles drawn ftill clofer together by their mutual attraction, they become ftill harder and more tranfparent, till they acquire, by a length of years, their greateft degree of perfection. As to the Briftol ftones being found of fuch different flzeg; I am induced to think they grow larger or continue fmall, only by the accident of the moifture bringing falts to them fafter or flower ; for had they any other regular method of growing, I think they ought never to be found in their moft perfedt ftate, till they had firft acquired their full bulk; vyhereas, on the contrary* they are found in their gi'eateft degree of perfection of all fizes. 1 therercrelmagine, that, till the outfide furface is .hardened, whatever addition of -falts is made will increafe, the bulk of the ftone ; but that, after the outward furface is once hardened, the addition of falts then only helps to bring it to its moft perfeCt trans- parent ftate;. and therefore, that when the flow of moifture or vapor, and confequently the addition of .falts, is very quick, there (the outward furfaces not having time to harden till a confiderable quantity of falts are accumulated together) the ftone, will grow lunre; O ’ I [ 63.] large ; bat where the flow of moifture is flow, tuei>- (the outfide Surfaces, and indeed the whole maSs, becoming hard before a frefh fupp’iy of Salts is addeu) the ftones will be Small. And again, where the moifture and faits pafs through large pores, theie tne cryftal, or fpar, or other concretion, will be very imperfect, being mixed with much heterogeneous, matter; but where, the moifture., .and cryftallizing particles, or faits, defeend though very minute pores there the faits will be moft unmixed and pure, and the cryftal or ftone will be of the moft transparent kind In fhort, I cannot but look upon the largeft caverns in the earth, and the fmalleft cavities in ftone, as producing fimilar effects, and therefore co.nfideL them in the fame light. In thefe conclufions I may perhaps be mittalcen, but they are at leaft; confiftent with the observations we make : for wherever there are cavities in the earth,, or in ftones, into which moifture can any way delcena, we almoft always find thefe kind of cryftallizations and concretions ; and the more plentiful the moifture is, and the more porous the ftrata of earth or ftones are through which it pafles, the larger the concretions are, and the more remote from a tranfparent ftate.j as appears in thofe great caverns in the Peak, and in Somerfetfhire, &c. Whereas, on the contrary, the harder and lei's porous the fubftance is through whicn the moifture paffes, the more transparent are the ftones formed by it, as in the cafe of Briftol ftones, and of feme of thofe beautiful fpars adjoining to veins of ^Whether all kind of ftones may not be formed m Somewhat the fame manner, by the water carry mg [ 6+ ] the ftony particles to the fame place, and their col- lecting there together, by their mutual attraction, I leave to others to determine j but I am much per- fuaded, that this may probably be the manner of the production of fpars and cryftals : and perhaps jewels, or precious (tones, may grow juft in the fame way ; and owe their perfection folely to their being compofed of ftill more minute falts, and more (lowly ; whence we may conjecture, why it is fo rare to find large diamonds. I have 'obferved fome of the Briftol (tones to have a fine purple appearance, like an amethyft ; and it is well known, that feveral forts of fpars are of various beautiful colors, by means of a mixture of mineral particles, in which they have a diftant re- femblance of jewels j and indeed they feem to be very analogous to them in many refpeCts. After all, however, I am fenfible that what I have advanced deferves not to be confidered as any thing more than mere guefs. I know that a confirmation of the truth of thefe conjectures muft depend upon ex- periments, which I have it not in my power to make: and I can only conclude with wishing, that fome gen- tlemen, converfant in chemiftry, may fome time or other attempt to analyze thefe bodies, and to fee whether they really are compofed of what may pro- perly be called falts, and of what kind. It is much to be lamented, that, in enquiries into the nature of foftils, there have not been more che- mical experiments made. 1 VI. Experiments k [ 65 ] Received October io, 1766. VI. Experiments with Camphire , by- Mr. Alexander, Surgeon in Edinburgh. S medical authors have differed fo widely in their opinions concerning the nature and effedts of camphire, one part of them positively affirming that it heats, and another aflerting with the fame confidence that it cools the body ; I made the following experiments with it, in order, if poffible, to have cleared up the difficulty. If camphire was a heater, I concluded it would raife my pulfe, and augment my natural heat ; and therefore, previous to my taking it, I counted the number of pulfations in a minute, which were fixty- eight, and found that, in the fpace of five minutes, the mercury in Fahrenheit’s thermometer arofe eighteen degrees by the heat of my Stomach Having thus found the State of my pulfe, and of my natural heat ; I took 9j of camphire in a little of the pulp of tamarinds ; and twenty minutes afterwards applied the thermometer to my Stomach : the mercury, in the fpace of five minutes, arofe exadly eighteen degrees, as it had done before taking the dofe, but my pulfe beat only fixty-fix, which was two Strokes lefs. Three quarters of an hour after I had taken the camphire, I applied the thermometer again j in the * The thermometer was applied to the pit of my Stomach. Vol. LVII. K fame [ 66 ] fame fpace of time, the mercury arofe exadlly the fame as in the laft trial, but my pulfe beat only fixty-five which was one ftroke lefs, and three fewer than it had done before I took the camphire. The next day, having found that the mercury arofe nineteen degrees in five minutes, by the heat of my ftomach j and that my pulfe beat feventy-feven in a minute, I took E)ij of camphire in a little of the fy- rup of palerofes: immediately after fwallowing it, I felt a fenfation in my mouth Something fimilar to that occafioned by ftrong peppermint-water, but much more difagreeable j ten minutes after I had taken it I applied the thermometer to my ftomach ; in five mi- nutes the mercury arofe eighteen degrees, which was one degree lefs than it had done before I had taken it. My pulfe now beat only feventy, whereas before I took the dofe it had beat feventy-feven : five and twenty minutes after I had taken it, I applied the thermometer again, and the mercury arofe the fame as at the laft trial, but my pulfe had increafed from feventy to feventy-feven, the exa her temples, and under the chin ; immediately on her parting with which, die, involuntarily, daook her Vol. LVII. N head. [ 90 ] head, making her ufual noife, in endeavouring to ipeak. The next day, I fixed the condudtor round her temples, and throat, and gave flight fhocks, by touch- ing fometimes her chin, othertimes her teeth or cheeks, with the communicant wire. This fhe difa- greeably, though advantageoufly, felt, her jaws hereby admitting their being opened a little. The next day, I (the gnomon being near ered!) increafed the fhocks conflderably, by which, though lhe very difcontentedly bore them, the became capa- ble of opening her mouth to the width of an inch, and of articulating an imperfedt, though, with diffi- culty, an intelligible found. ^ The next day, (the index quite perpendicular) Jhe very reludfantly received feveral fmart ffiocks, and at laft unexpectedly (the air being very electric) to iiich a degree, as to deprive her of her fenfes ; fhe becoming thereon, and remaining for half an hour, flrongly convulfed. 1 he next day, after the firft fhock, fhe fpoke fo as to be tolerably well underflood, telling us that the fhocks were frequently vaftly fevere for her to bear; but that, as fhe was fully ienfible of the advantage flie had already received thereby, fhe would gladly lubmit to my will, in hopes of a further advantage. She was even now incapable of bringing "her tongue without her teeth, and of moving it without great difficulty, complaining it feemed very large, and heavy. On infpeding her mouth, which fhe was able to open to almofl its ufual width, I difeovered nothing particular. C 91 ] particular, but an extraordinary turgefcence, without induration, of the fubiingual glands. After this (lie received about twenty fhocks daily on her tongue, and other parts, for a fortnight, by which time all her complaints were removed, and fhe returned home quite well, and has remained fo ever fince, N. B. In the firft week’s experiments, the fhocks were confined between her hip, and foot, of the right fide ; after that, on various parts, as judged requifite : her tongue, at its tip, became very red, and tender, after the firfl electrization, its papilla appearing very prominent ; and its fubjacent glands foon leffened their bulk, her mouth running greatly with faliva : her pulfe, with a (hock or two, generally quickened twelve or fourteen times per minute. She, after grown tolerably well, immediately on having a fmart eleCtrical ftroke, frequently became, for fome fmall time, as paralytic as ever on her right fide ; and fome- times, thereon, had a return of her fits, the going oft of which were attended with profufe fweats. Her blood appeared of a good texture, otherwife than giving off a little more than its due proportion of latex. N 2 XI. Expert- [ 92 ] Received December n, 1766. XI. Experiments on Rathbone-Place TV ater : By the Hon. Henry Cavendifh, F. R. S. Read Feb. Lucas has given a fhort exami- l;6?’ 1 3 nation of this water in the firft part of his treatife of waters. It is the produce of a large fpring at the end of Rathbone-place, and ufed a few years ago to be railed by an engine for fupplying part of the town. The engine is now deftroyed ; but there is a pump, nearly in the fame fltuation, which yields the fame kind of water. It is the water of this pump, which was ufed in thefe experiments. Moll: waters, though ever fo tranfparent, contain fome calcareous earth, which is feparated from them by boiling, and which feems to be dilfolved in them without being neutralized by any acid, and may therefore not improperly be called their unneutralized earth. The following experiments were made chiefly with a view of enquiring into thecaufe of thefufpenfion of this earth, for which purpofe this water leemed well adapted ; as it contains more unneutralized earth than molt others. Thefe experiments were made towards the latter end of September 1765, after a very dry fummer ; whereby the water was moft likely more impreg- nated with faline and other matters than it ul'ually is. The [ 93 ] The water, at the time I ufed it, looked rather foul to the eye. On expofing fome of it for a few days to the open air, a fcurf was formed on its furface, which was nothing elfe but fome of the unneutralized earth feparated from the water. - On dropping into it a folution of corrofive fublimate, it grew cloudy in a fewfeconds; it quickly became opake, and let fall a fediment. This is a property, which I believe does not take place, in any confiderable degree, in moll of. the London waters. Experiment I. 494 ounces of this water were diflilled in a copper ftill, till about 150 oz. were drawn off. A good deal of earth was precipitated during the diftillation, which being colle&ed and dried, weighed 271 grains. It proved to be entirely a calcareous earth, except a fmall part, which was magnefia. This I found in the following manner. A little of this earth, being mixed with Spirit of fait, diffolved entirely j which fhews it to conlift folely of an abforbent earth, but does not {hew whether it is a calcareous earth or magnefia. The remainder was faturated with oil ot vitriol : a great deal of matter remained undiffolved, which, as the earth was {hewn to be entirely of the abforbent kind, muff have been felenite,or a calcar ious earth faturated with the oil of vitriol. The clear liquor {trained from off the felenite yielded on evaporation only eighteen grains of folid matter, which proved to be Epfom fait j fo that all the earth, except that contained in the eighteen grains of Epfom fair, muff have been of the calcareous kind. That contained mu the Epfom fait is well known to be magnefia. r The 6 C 94- ] ^ The water remaining after diftillation, and from which the earth was feparated, was evaporated, firffc in a fiiver pan, and afterwards in a glafs cup, till it was reduced to about three ounces. Not the leaft earth was precipitated during the evaporation, till it was reduced to a fmall quantity ; there then fell 39 grains, which were entirely felenite: fo that all the unneu- tralized earth in the water was feparated during the diftillation. The liquor thus evaporated was of a reddifh colour, like an infufion of foot. Many waters contain a good deal of neutral fait compofed ot the nitrous acid united to a calcareous earth ; the molt convenient way of afcertaining the quantity of which, is to drop a folution of fixed alcali into the evaporated water, till all the earth is preci- pitated 5 whereby this fait is changed into true nitre, and is capable of being cryftallized. For this reafon, fome fixed alcali was dropt into the eva- porated water till it made no farther precipitation. The earth precipitated thereby weighed thirty-fix grains, and was entirely magnefia. The liquor was then farther evaporated, but no nitre could be made to fhoot : being then evaporated to drynefs, it weighed 256 grains. It gave not the lead figns of containing any nitrous fait, either by putting fome of it upon lighted charcoal, or by making a match with a folution of it, but appeared to be a mixture of fea fait and vitriolated tartar, or fome other fait compofed of the vitriolic acid. As I have heard of no other London water, that has been examined with this view, but what has been found to contain a confidcr- able proportion of nitrous fait, it feems very remark- able that this fhould be intirely deflitutc of it. I now proceed [ 95 ] proceed to the experiments made on the difiilied water. The difiilied water, efpecially that part of it which came over firfi, became opakefand let fall a precipitate, on droping into it a folution of fugar of lead. It alfo became opake by the addition of corrofive fublimate, much in the fame manner that the plain water did before diftillation. It was found, by dropping into it a little acid of vitriol and committing it to evaporation, to contain a fmall quantity of volatile alcali; as it left four grains of a brownifh fait, which being re-diflolved in water, yielded a fmell of volatile alcali on the addition of lime. It is doubtlefs this volatile alcali, which is the caufe of the precipitate, which the difiilied water makes with fugar of lead and corrofive fublimate. What firfi fuggeffed to me that the difiilied water contained a volatile alcali, was the diddling feme of it over again in a retort ; whereby the firfi: runnings were fo much impregnated with volatile alcali, as to turn paper died with the juice of blue flowers, to a green colour, and in fomemeafure to yield a fmell of volatile alcali. In the foregoing experiment, the fait procured from the difiilied water was perfectly neutral ; fo that the quantity of acid employed was certainly not more than fufficient to faturate the alcali, but it may very likely have been lefs ; as in that cafe the fuperfiuous volatile alcali would have flown off in the evaporation. The following experiment fhews pretty nearly the quantity of volatile alcali in the difiilied water,. Experi- [ 96 j Experiment IT. 1 1 28 ounces of Rathbcne-place water were (Mil- led in the lame manner as the former. The diflilled water was divided into two parcels, that parcel which came over firft weighing 12 1 ounces, the other 146. A preparatory experiment was firft made, in order to form a judgement of the comparative ftrength of each parcel, and alio of the quantity of acid which it would require to faturate them. This was done by dropping l'ugar of lead into each parcel till it ceafedto make a precipitate. It was judged from hence that the firft parcel contained about 2.4 times as much volatile alcali as an equal quantity of the fecond. Into 30 ounces of the firft parcel, mixed with as much of the fecond, was then put 43 grains of oil of vitriol, which was fuppofed to be about 4 more than fufticient to faturate the alcali therein. The mixture was then evaporated. When reduced to a fmali quantity, it was found to be rather acid : fixteen grains of volatile fal ammoniac were therefore added, which feemed nearly fufticient to neutralize it. Being then evaporated to drynefs, it left fixty-fix grains of a brownilh fait, which diftolved readily in water, leaving only a trifling quantity of brown fediment. A little of this fait was found to make no precipi- tate on the addition of fixed alcali, and the remainder, being boiled with lime, was converted into felenite ; a fure fign that the fait was merely vitriolic ammoniacal fait. The volatile alcaline fait contained in fixty-fix grains of vitriolic ammoniacal fait is 584. grains ; from whence deducing fixteen grains, the weight of the volatile fal ammoniac added, it appears that the diflilled water C 97 ] water ufed in this experiment contains 42I grains of volatile fait j and therefore the whole quantity of volatile fait driven over by diflillation feems to be about fixty-eight grains, which, as the fecond parcel was fo much weaker than the firft, is probably nearly the whole volatile alkali contained in the water. Experiment III. Dr. Brownrig, in a paper printed in the Philofophi- cal Tranfa&ions, for the year 1765, fhews that a great deal of fixed air is contained in Spa water. This induced me to try whether I could not find any in that of Rathbone-place j which I did by means of the contrivanee reprefented in the drawing. [ 98 ] ACDE reprefents a tin pan, filled with Rathbone- p’ace water as high as BG. HKL is another tin pan, within the ffrfi, in the manner of an inverted funnel, and made in fuch a manner as to leave as little room as poffible between that and the fides of the outward veffel. M reprefents a bottle, full of the fame water, inverted over the mouth of the funnel. By this means, as faff as the air is difengaged by heat from the water within the funnel, it muff neceffarily rife up into the bottle. The Rathbone-place water, put into the veffel, weighed 41 1 ounces, the funnel held 353 ounces. A bottle full of water being inverted over the mouth of the funnel, as in the figure, the water was heated, and kept boiling about 4 of an hour. As foon as one bottle was filled with air, it was removed by putting a fmall ladle under its mouth, while under water, and fet with its mouth immerfed in the fame manner in another veffel of water, taking care not to fuffer any communication between the included air and the outward air during the removal. At the fame time, another bottle full of water was inverted over the mouth of the funnel,, in the fame manner as the former. It was not eafy tel.ling how much air was discharged from the water j as the air in the bottles, when firff removed, was hot and expanded ; and, before 1 could be fure it was cold, there was fome of it abforbed by the water : but there feemed to be above 75 ounce meafures difcharged, fcarce twenty of which arofe before the water began to boil. The water continued difcharging air after the experiment was discontinued. In about a day’s time, much the greateft part of the air was abforbed, fcarce fixteen u nee meafures remaining. That which was abforbed appeared to be fixed air, as the water which bad abforbe d C 99 1 abforbed it made a precipitate with lime-water. But, in order to abforb all the fixed air more perfectly, the air which remained not abforbed was transferred into another bottle of water, in the manner defcribed in my firft paper on factitious air, page 142 of the pre- ceding volume. This bottle was then fet with its mouth immerfed in a bottle of fope-Ieys ; after which, by fhaking the bottle, the fope-leys was mixed with the included water; whereby the air in the bottle was brought in contact with the fope-leys, which is well known to abforb fixed air very readily. By this means the air was reduced to 84 ounce meafures. A fmall vial being filled with equal quantities of this and inflammable air, and a piece of lighted paper applied to its mouth, it went off with as loud a bounce, as when the fame vial was filled with equal quantities of common air and inflammable air. The fpecific gravity of the remainder was tried by a bladder, in the manner defcribed in the above-mentioned paper ; as well as could be judged from fo fmall a quantity, it wasjufl the fame as that of common air. From thefe two circumftances, I think we may fairly conclude that this unabforbed part was intirely common air; confequently the air difcharged from the Rathbone-place water confided of 84 ounces of common air and about 66 of fixed air. The air which was difcharged before the water began to boil contained much more com- mon air, than that which was difcharged afterwards ; that which was difcharged towards the latter end feeming to contain fcarce any but fixed air. As fo much fixed air is difcharged from this water by boiling, it feemed reafonable to fuppofe, that the diftilled water fhould contain fixed air. I accordingly found it to make a precipitate with lime-water. O 2 Expe- [ 100 ] Experiment IV. The following experiment fhews that the fixed air was not generated during the boiling, but was con- tained in the water before. Into 30 ounces of Rathbone-place water was poured fome lime-water, which immediately made a precipitate. More lime- water was added, till it ceafed to make any farther precipitate. It required 2cJL ounces. The precipi- tated earth being dried weighed 39 grains. The unneutralized earth contained in 30 ounces of Rathbone-place water is 16 1- grains, and the earth contained in 201. ounces of lime-water (as was found by precipitating the earth by volatile fal ammoniac) is 2 1 grains. Therefore the earth precipitated from the mixture of Rathbone-place water, and lime-water, is about equal to the fum of the weights, of the earth contained in the lime-water, and of the unneutralized earth in the Rathbone-place water ; and consequently all the un neutralized earth feems to be precipitated from Rathbone-place water by the addition of a proper quantity of lime-water. But a more convincing proof that this is the cafe, is that the clear liquor, after the precipitate had fubfided, did not depofit any earth on boiling, or become in the leaf! cloudy on the addition of fixed alkali ; whereas Rathbone-place water in its natural date becomes opake thereby. It might perhaps be expended, that the clear liquor Should Hill make a precipitate on the addition of fixed alkali, though the unneutralized earth is precipitated ; as in all probability there is Still a good deal of earth remaining in it in a neutralized date. The realbn why it does not, feems to be, that the remaining earth is mod likely intircly magnefia ; and Epfom fait. E 101 ] fait, when dilToIved in a great quantity of water, does not make any precipitate on the addition of fixed alkali. There is great reafon to fuppofe that the earth preci- pitated on mixing the Rathbone-place water and lime- water, was very nearly faturated with fixed air, i. e. that it contained very near as much fixed air, as is na- turally contained in the fame quantity of calcarious earth. If fo, 30 ounces of Rathbone-place water contain as much .fixed air as 39 grains of calcarious earth ; whereas the unneutralized earth, in that quantity of water, is only 164. grains ; fo that Rathbone place water con- tains near 2 4 times as much fixed air as is fufficient to faturate the unneutralized earth in it. It feems likely from hence, that the fufpenfion of the earth in the Rathbone-place water, is owing merely to its being united to more than its natural proportion of fixed air ; as we have fihewn that this earth is actually united to more than double its na- tural proportion of fixed air, and alfo that it is im- mediately precipitated, either by driving off the fuper- fiiuous fixed air by heat, or abforbing it by the ad- dition of a proper quantity of lime water. Calcareous earths, in their natural ftate, i. e. fatu- rated with fixed air, are totally infoluble in water ; but the fame earths, entirely deprived of their fixed air, i. e. converted into lime, are in fome meafure foluble in it ; for lime-water is nothing more than a folution of a fmall quantity of lime in water. It is very remarkable, therefore, that calcareous earths fihould alfo be rendered foluble in water, by fur- nifhing them with more than their natural propor- tion of fixed air, i. e. that they fhould be rendered foluble, both by depriving them of their fixed air, [ 102 ] and by furnishing them with more than their natural quantity of it. Yet, ftrange as this may appear, the following experiments, I think, Shew plainly that it is the real cafe. Experiment V. In order to fee whether I could fufpend a calcareous earth in water, by furnilhing it with more than its natural proportion of fixed air, I took 30 ounces of rain water, and divided it into two parts : into one part I put as much fpiiit of fait, as would difiolve 3°tV grains of calcareous earth, and as much of a Saturated Solution ol chalk, in Spirit of fait, as con- tained 20 grains of calcaroeus earth : into the other part I put as much fixed alkali, as was eauivalent to 46 -,V grains of calcareous earth, i. e. which would Sa- turate as much acid. This alkali was known to con- tain as much fixed air as 39 grains of calcareous earth. The whole was then mixed together and the bottle immediately flopped. The alkali was before Said to be equivalent to 46 _8y grains of calcareous earth, and was, therefore, Sufficient to Saturate all the Spirit of fait, andalfo to decompound as much of the Solution of chalk as contains 164. grains of earth. This mixture, therefore, fuppofing I made no miflake in my calculation, contained 164. grains of unneutralized earth, with as much fixed air as is contained in 39 grains of calcareous earth ; which is the quantity which was found to be in the fame quantity of Rath- bone place water. The mixture became turbid on firft mixing, but the earth was quickly re-diffiolved on fhaking, fo that the liquor became almoh trans- parent. After handing Some time, a flight Sedi- ment fell to the bottom, leaving the liquor perfectly trail (parent. [ I03 ] tranfparent. The mixture was kept three or four days flopped up, during which time it remained perfe&ly clear, without depofiting any more fediment. The clear liquor was then poured off from the fediment, and boiled for a few minutes, in a Florence flafk ; it grew turbid before it began to boil, and difcharged a good deal of air ; fome earth was precipitated during boil- ing, which being dried weighed 13 grains. This fhews that there was really, at lead 13 grains of earth fufpended in this mixture, without being neutralized by any acid ; the fufpenfion of which could be owing only to its being united to more than its natural proportion of fixed air. But, as a further proof of this, I made the following experiment. Experiment VI. I took the fame quantities of rain water, folution of chalk, fpirit of fait, and fixed alkali, as in the laft experiment, but mixed them in a different order. The fixed alkali was firft dropped into the fpirit of fait, and when the effervefcence was over, was di- luted with 4. the rain water. The folution of chalk was then diluted with the remainder of the rain water, the whole mixed together, and the bottle immedi- ately flopped, and lhook vehemently. . A precipi- tate was immediately formed on mixing, which could not be re-diffolved on fhaking. It muff be obferved, that, in the firfl of the two foregoing experiments, all the fixed air contained, in the alkali was retained in the mixture, none being loft by effervefcence ; whereas, in the laft experi- ment, the greateft part of the fixed air was diflipated in the effervefcence) no more being retained than what [ io4 ] what was contained in that portion of the fixed alkali, which was not neutralized by the acid ; and con- fequently the unneutralized earth, in the mixture, contained not much more fixed air than what was fufficient to faturate it. As the latter of thefe mix- tures differed no otherwife from the former, than that it contained lefs fixed air ; the fufpenfion of the earth in the former muff neceflarily be owing to the fixed air. In the two foregoing experiments the water con- tained, befides the unneutralized earth, and fixed air, lome fill fylvii, and a little folution of chalk in the marine acid ; which, it may be fuppofed, contri- buted to the fufpenfion of the earth : but the follow- ing experiment fhews that a calcarious earth may be Impended in water, without the addition of any other fubffance than fixed air. Experiment VII. A bottle full of rain water was inverted into a yefiel of rain water, and fome fixed air forced up into the bottle, at different times, till the water had abforbed as much fixed air as it would readily do ; 1 1 ounces of this water were mixed with 6 _L of lime water. The mixture became turbid on "firff: mixing, but quickly recovered its tranfparency, on fhaking, and has remained fo for upwards for a year. This mixture contains 7 grains of calcareous earth; and, from a fubfequent experiment, I guefs it to con- tain as much fixed air, as there is in 14 grains of calcareous earth. Experiment VIII. Leaft it fhould be fuppofed, that the reafon why the earth was not precipitated in the foregoing experi- 2 ment, [ I05 ] ment, was, that it was not furnilhed with a fufficient quantity of fixed air, the following mixture was made, which contains the lame proportion of earth as the former, but a lefs proportion of fixed air: 4 ^ ounces of the above-mentioned water, containing fixed air, were diluted with 6 i. of rain water, and then mixed with 6 ounces of limewater. A pre- cipitate was immediately made on mixing, which could not be re-diffolved on fhaking. Experiment IX. I made fome experiments to find whether the un- neutralized earth could be precipitated from other London waters, by the addition of lime water, as well as from Rathbone-place water. It is neceffary for this purpofe, that the quantity of lime water Ihould be adjufted very exactly ; for, if it is too little, it does not precipitate all the unneutralized earth ; if it is too great, fome of the earth in the lime water re- mains fufpended. For this reafon, as I found it al- moft impoffible to adjuft the quantity with fufficient exactnefs, I added fuch a quantity of lime water, as I was well allured, was more than fufficient to pre- cipitate the whole of the unneutralized earth ; and when the precipitate was fubfided, decanted off the clear liquor, and expofed it to the open air, till all the lime remaining in the water was precipitated, by attracting fixed air from the atmofphere. The clear liquor was then decanted and evaporated, which is much the molt exact way I know of feeing whe- ther any unneutralized earth remains fufpended in the water. The refult of the experiments was as follows : Vol. LVII. P 200 [ 2°6 ] 200 ounces of water, from a pump in Marlbo- rough-ftreet, were mixed with 38 ounces of lime water. The earth precipitated thereby weighed 38 grains. The clear liquor, expofed to the air, and evaporated in a filver pan till it was reduced to 6 or 7 ounces, depofited no more than 2 or 3 grains of unneutralized earth. A like quantity of the fame pump water, evaporated by itfelf without the addition of lime water, depo- fited about 19 grains of unneutralized earth. 200 ounces of water, from a pump in Hanover- fquare, being mixed with 67 ounces of lime water, the precipitate weighed 93 grains. The clear liquor, treated in the fame way as the former, depofited about 2 grains of earth. 200 ounces of the fame wa- ter, evaporated by itfelf, depofited 28 grains of earth. The fame quantity of water from a pump in St. Martin’s church-yard, being mixed with 82 ounces of lime water, the precipitate weighed 108 grains. The clear liquor depofited fcarce any unneutralized earth on evaporation. The fame quantity of water, evaporated by itfelf, yielded 45 grains of unneutralized earth. The way, by which I found the quantity of un- neutralized -earth depofited on evaporation, was, after having decanted the clear liquor, and wafhed the refiduum with rain water, to pour a little fpirit of fait into the filver pan, which difl'olves all the calca- reous earth, but does not corrode the filver. Then, having feparated the folution from the infoluble mat- ter, the earth was precipitated by fixed alcali. In this way of finding the quantity of unneutralized earth, care muft be taken to add very little more * acid [ *07 ] acid than is neceflary to diffolve the unneutralized earth, and to ufe as little water in washing out the folution as poffible; for otherwife a good deal of the felenite, which is depofited in the evaporation of mod: water, will be diffolved ; the earth of which will be precipitated by the fixed alcali, and by that means make the quantity of unneutralized earth ap- pear greater than it really is.. It appears from thefe experiments, that the un- neutralized earth is intirely precipitated from thefe three waters, by the addition of a proper quantity of lime water; as the' trifling quantity found to be de- pofited, on the evaporation of two of them, mod likely proceeded only from not expofing the water to the air, long enough for all the lime to be precipitated. So that I think it feems reafonable to conclude, that the unneutralized earth, in all waters, is fufpended merely by being united to more than its natural pro- portion of fixed air. To return to Rathbone-place water; it appears from the foregoing experiments, that one pint of it, or 7315 grains, contains, fird, as much volatile al- cali as is equivalent to about grains of volatile fal ammoniac : fecondly, 8 grains of unneutralized earth, a very fmall part of which is magnefia, the red a calcareous earth : thirdly, as much fixed air, including that in the unneutralized earth, as is contained in 19 grains of calcareous earth: fourthly, 1 of felenite: fifthly, 7 Jl of a mix- ture of fea fait, and Epfom fait; and the whole fo- lid contents of 1 pint of the water is 17 4. grains^ One pint of water, from the pump in Marlbo- rough-dreet, contains 1 T%_. grains of unneutralized d P 2 earh [ 108 1 earth, and as much fixed air as is contained in 2 TV grains of calcareous earth. The fame quantity of water, from the pump in Hanover-fquare, contains 2 grains of unneutra- lized earth, with as much fixed air as is contained in 7 of earth. The fame quantity of water, from St. Martin’s Church-yard, contains 3 grains of unneutralized earth, with as much fixed air as is contained in 8 of earth. „ , .... — ■ ' 1 - — Received November 18, 1766. XII. Defcription of a Meteor feen at Oxford, O&ober 12, 1766. In a Letter to Charles Morton, M. D. Sec . R . S. from the Rev. John S win ton, B. D . F. R. S . Meinber of the Academy degli Apatifti at Florence, and of the Etrufcan Academy of Cortona in Tufcany. Dear Sir, % Head Feb. 26, rpHE Reverend Dr. Sharp coming 1767. -nto chrift-Church common- room out of the great quadrangle, on Saturday, Octo- ber 12, 1765, about 8h 30' P. M. informed the com- pany there, that he had feen fome remarkable Aurora Boreales a few minutes before. But, as fuch pheno- mena 4 ' i »»Vfc v*0 1 . n '« - *J - T; . /. tfyntfr [ 109 ) mena are common enough here, they gave little atten- tion to the information. However, being upon the ter- race, about 8h 45' P. M. I difcovered (See Tab. V. *) a broad luminous arch, in the northern part of the he- mifphere, extending from E. to W. almoft terminated by the horizon, and fomewhat lefs than a femicircle. The upper or exterior limb of this arch, together with a certain portion of the lucid adjoining tra£t, was white and refplendent; but the brightnefs gradually de- creafed as it approached the lower or interior limb, which was fo fufcous and obfcure, that it feemed fcarce diftinguifhable from the clouds that were con- tiguous to it. For about five minutes, the luftre re- mained pretty ftrong and vivid, and the meteor with- out any vifible change or variation ; but, after the expiration of that fhort term, the arch begaJn to grow faint, and in one or two minutes more, as near as I can guefs, totally difappeared. How long this meteor had been formed, when I firft obferved it, I cannot take upon me to fay ; but I believe it was then, and perhaps for fome time had been, upon the decline. It was feen by the Reverend Mr. Selftone and the Reverend Mr. Beft, chaplains of Chrift-Church, as well as by other members of the Univerftty, not without fome degree of wonder and furprize. The crepufculum, or illuftration of the atmofphere, which fometimes precedes fuch meteors as that defcribed here, and even continues long after their extin&ion, might perhaps have remained till ten or eleven o’clock ; which if we admit, this crepufculum may not improbably be confidered as the fame phenomenon with “ the furprizing << bright * luminous appearance vifible at London in * Lloyd’s Evening Poji , &c. No. 1289. p. 365. the [ 110 ] ^2 ■ ^ ■ XIV. ^ Defcription of the Andrachne , w/V/r //j’ Botanical Char aiders: By G. D. Ehret, F. R. S. -km Read Feb. 2 6, TT^ ROM a fhort and crooked ftem go . X1 off irregularly feveral branches bend- ng in various directions ; but the younger fhoots, moffly pointing upwards. The height of°the fhrub is now about four feet. The item and branches are of different colours at. different feafons. In the fpring, they appear of a greenifh cinnamon colour; this is gradually heightened to almoft a red during winter; towards the end of which, the epidermis peels off, and the new bark ex- hibits the likeappearance as it had the fpring before. On the extremities of thefe branches, the fhoots of the preceding year, which are of a deep red colour, are many leaves of different frzes, placed irregularly ; the large ft leaves were in length,- when the figure was drawn, about four inches* and two inches and an half in breadth, of an oval figure : they are moftly entire, though the edges of fome are. lightly ferrated : their lurface is fmooth and lively, but not gloffy or fhining. They are fupported on the branches by foot! talks about an inch long, of a red colour and* fmooth, The young leaves, at their firft appearencc, are of a faintifh green with a caft of yellow yet beautifully fhaded with red : their footftalks and middle rib are 1 then Fbi/os, Ihans. VbJ . ZVH. TAli. IT. p. ug [ “5 1 then hoary, but they lofe this appearance as they -grow older. 1 his very rare fhrub produced its flowers, for the •firft time in England, in the garden of Dr. John Fothergill, at Upton near Stafford in Effex, May 1766. The principal fpikes of flowers in this fpecies of arbutus are eredt, producing many fide ones in a horizontal direction, their extremities inclining down- O wards. Each of thefe Ample ramifications contain many white globular flowers, hanging on long hoary glutinous pedunculi, which are lituated alternately. Thefe fpikes of flowers, forming a kind of loofe tuft with the bright bunches of leaves, form an elegant appearance. Characters of the Flower. TAB. VI. Fig. a. reprefen ts a fide view of the flowers ; they are of a globular fhape, and open into five obtule reflex lacinias, in the manner of die common arbutus. Fig. b. a back view of the flower, upon which appears the calyx fpread open, and clofely adhering to the flower ; it con fills of live oval pointed leaves or divifions ; around this calyx appear on the corolla ten yifible nedtaria. When thefe flowers drop off, the calyx clofes up, and embraces the tender germ. See Fig. c. Fig. d. reprefents a flower fcparated from the calyx ; it is inlerted at the bale of the germen. The ten nedtaria, which are fomewbat fwollen or raifed from the corolla, and have transparent appearances, are 2 alfo I 116 ] alfo discoverable, whilft the magnified figure e fays the parts more diftindtly in view. This is a remarkable character in this flower. Fig.y. exhibits the flower laid open: it is finooth without, and hoary within j it contains ten ftamina, which are infer ted at the bale of the flower, their filaments and apices embrace half the ftyle. l?Jg* S’ two fiamina magnified, the bafe whereof is a tender flefhy lubftance, hoary and of a club-like fliape j this diminifhes gradually into a filament, upon which is lituated a fingular anthera; this anthera burfls at two apertures (as the figure reprefents), and dilperfes.its farinaceous duft towards the ftyle : from the top of this apex, comes forth, at the oppofite fide, two crooked forked horns, bending downwards in length of the antera. Fig. h. the germen or rudiment magnified. This is hoary, its bafe confifts of a red flefhy fubftance, with ten obtufe angles. The ftyle fupports a fmall globular ftigma, and does not exceed the length of the flower. Fig. i. reprefents a horizontal view of the germen, as obferved through a lens ; it has five regular iocula- ments or cells, though ieemingly but one feed; but by a clofer infpedfion, there appeared feveral embryo feeds in each cell. Fig. k. a dried fruit or berry of the andrachne in its natural fize, with an horizontal fedtion. This fruit, which is tuberculous, I drew from a fpecimen con- fifting of the whole branch, leaves, flower-fpikes.with many ripe berries which was brought from Aleppo, by Dr. Alexander Rufiell ; all which I examined and ueferibed at that time for my own fatisfa&ion, and find 5 [ ”7 ] find them to agree exa&ly with the recent fhrub above defcribed. It likewife Teems worthy of obfervation, that the plants railed by the gardiners by grafting or inarching the andrachne upon the common arbutus, which is the method chiefly ufed in propagating this elegant fhrub, differ confiderably from the plants raifed from feed, particularly in this, that the young branches, and the footfealks of the leaves, are very hairy,and the leaves themfelves are all without excepti- on deeply ferrated like the arbutus. Dr. Ruffellalfo informs me, that the outer bark of the old Item and branches abroad, are for fome months of the year of as beautiful a crimfon, as the young {hoots are here defcribed to be, and doubts not but it will be fo in this country, as the fhrub grows older *. It may not be Improper to mention, that the flower fpike above defcribed, with the glandular prominences, which were the rudiments of future flowers, made their appearance foon after Midfummer 176^ : they advanced very flowly during the remains Oi fummer ; flood the winter under a flight cover, and made no great progrefs, till within a month of their flowering. That plant, which produced thefe flowers, was one of feveral, which J. Gordon, of Mile-end, was fortunate enough to raife from feed, fent by Dr. Ruflell from Aleppo in 1754; and that this fhould be the only plant which has hitherto pro- duced flowers, is probably owing principally to its having been divers times tranfplanted. XW. nifiory C "8 ] Received December 20, 1766. X\ . Hiflory of a Feet us born with a very imperfeSl Brain ; to which is fubjomed a Supplement of the EJfay on the Ufe of Ganglions , publifhed in Philof. Eranf, for 1 7O4 .• By James Johnfton, M. D. ■Rcad March s,yN 0<3ober 27, ,765, a monftrous birth ‘ X was brought me by a midwife of this place. It was a female child come to its full time, in which the whole fcull excepting its balls was wanting : this was covered with fomething which had the ap- pearance of red flefh. I found it to confift of different membranes ; and in a fmall deprefiion, in a back part of the bafis of the fkull, lay the brain, fuch as it was, not exceeding the fize of the kernel of a filberd nut, flaccid and membranous. I could not have politively pronounced it brain, had I not traced its continuation into fpinal marrow, down the channel of the vertebrae. The eyes were perfect and found. The optic nerve of one eye I examined, though not large enough, yet in thicknefs was almoft equal to one third of the fpinal marrow, which was too fmall like wife. Upon opening the bread: and abdomen, all the organs contained therein feemed in ttru&ure perfect, properly fituated and full grown. The heart in par- ticular was plump and firong. This infant had not breathed. [ rl9 ] breathed; its lungs, which were perfect, funk in water: yet the mother and midwife felt it active and ftrong .juft before delivery. This child had tongue, noftnls, eyes, and ears, and every other part, excepting the brain, perfect and plump, as in the healthieft infants come to their full time. Many births ftmilar to this, in moft circumftances,- are recorded in the Transactions of the Royal Society, N5. 99. 2 26. 228. 242, 1. Such of them as were born alive, died foon after birth, though lively and ftrong in the womb, and perfect in all parts, the brain and fcull excepted. 2. In that of which an account is given by Dr. Prefton (Philof. Tranf. N°. 226.), the celebrated ana- tomift Monf. du Verney traced the eighth and ninth pairs, the medulla fpinalis, and the intercoftals. ihe child was well proportioned, the cranium, brain, and cerebellum were wanting ; in lieu thereof, remained only a fubftance, like congealed blood, covered witn a membrane. 3. In a cafe related, and largely-commented upon, by the celebrated Wepfer *, which differs in many refpe&s from other children faitl to be without brains ; the child was well proportioned, its head of the ufual fize,.but its brain had degenerated into veficles, or hyda tides, each of which had its blood veffel (might one from thence infer the natural flats of the cortical fubftance of the brain to be cellular?) and the optic and auditory nerves took their rile from three' portions of medullary fubftance lying upon the fphaanoid bone near the fella equina. * Mrarret Bib'iotb. Auift, Vol. II. p. 339; 4. Theft :: [ 12° ] 4* Thefe lingular exiflences afford ufeful in- ferences, and lhew that the irritability of the heart, is capable of being fuftained, by very low degrees of the nervous power, while that irritability is kept up by the foftering heat of the mother. This feeble life is foon extinguifhed, when the influences of the mother’s warmth and circulation ceafe (N°. j). Such infants die as fcon as born, or foon after.. .5. Such examples more confequentially than expe- riments demonftrate that the fpinal marrow is the principal origin of the intercoftal nerves (N°. 2.) ; and better than ligatures illuftrate their vaft importance, for, 6. From the plump ftate of the body, and vigo- rous appearance of the heart, it is evident the circu- lation, and the developement of the feveral organs, had been carried on properly in the foetus ; and that the irritability of the heart derived a fufficiency of nervous influence from the intercoftal nerves, and its ganglions, and thefe again from the fpinal marrow, tor growth, and that ftate ofexiftence. In the eftay which was publifhed in the Philof. Tranf. for 1764, I endeavoured to prove, that as ganglions are ieated conftantly on the intercoftal nerves, and on others fent to mu teles whofe motions are involuntary, and are very rarely fecn on nerves lent to voluntary mufcles, and not at all on the fenfory nerves ; it feems that, by means of ganglions, the motions of the heart andinteftines and uvea are render- ed uniformly involuntary. I was then, and am ftill ienfible that various ftrong objections may be made to this dodtrine, in common with every other lyfteni whatever t but efpecially every fyftem which pretends to C i2t ] to explain any thing relating to fo obfcure a part of the animal oeconomy, as the nerves, and their facul- ties. But as this dodrine, weighed againd what has been faid againd it, feems to me to have a confidera- ble preponderance of evidence and probability in its favor, I fhall now date the dronged objections which have been oppoled to it, and endeavour to anfwer them. i. The chief objedion which has been made to this dodrine arifes from obferving, that the fpinal nerves, have each one ganglion : and that one or two have been obferved fometimes upon the fubdivifions of the fifth pair of nerves. With refped to the fird, it is in the highed degree probable that the ganglion obferved upon each of the fpinal nerves refpeds folely the intercodals (fee Window’s; defcription of that nerve, Exp. An at. p. 462.) and is there feated to fet apart for the ufes of the great fympathetic nerves the farculi , which are- from each of thefe ganglions detached to that great pair of nerves. 1 . Becaufe the fpinal nerves have no other ganglion in any part of their courfe. 2. When nervous twigs are fent ofi' from the fpinal nerves, to join others befides the intercojlals, they have no ganglions ; as the nervi accejjorii fent from the upper fpinal nerves to join the eighth pair: and the fird of the fpinal nerves, and the lad of the nervi fa- cri are reprefented by Vieuflens * as being without ganglions , and fending no contribution to the inter- codals. Were the ganglions only little knots indifcriminate- ly fuitable for nerves, which carry the commands of * Neurography Vol.LVII.- R the £ 122 j v the will, and thofe which do not, one might expert them equally frequent on the nerves of the limbs, as at the rife and on the courle of the inter cojl ah , where they are numerous, large and conftant : on the nerves fent to the fenfory organs , and- on the phre- netic as well as the lenticular ganglion from which the Iris is provided with nerves. In a word the folici- tude, fo to exprefs myfelf, and the conftancy with which all parts whofe motions are involuntary are provided with nerves furnifhed and befet with gan- glions ; and the great fcarcity and rarity of them on nerves detached to mufcles fubjed to our volitions, and the total want of them on the fenfory nerves, fufficiently befpeaks their general diftindion and ufe, notwithstanding a few feeming exceptions. I fay feeming, becaule fome that are ailedged as exceptions are not permanently and conftantly found. To af- certain the ufe and importance of any part of animal jftrudure, we ought to be certain that it is conftantly found in that fituation ; if, on the contrary, it be only accidentally feen, and not perpetually, we can nei- ther a Sign any important ufe to it, or draw any im- portant dodrine from it, and have great reafon to fufped; it to be rather fome morbid phenomenon than otherwife. Now this is the cafe with refped to the ganglia defcribed by Mekelius as leated on twigs of the fecond and third branches of the fifth pair of nerves ; betwixt which and other ganglions Baron Haller makes a very cficntial diftindion, par- ticularly the ganglion ophthalmicum , which he fays is conftant and perpetual, whereas thefe beforemention- ed C 1 2s 3 ed are not fo, for he mentions his having examin- ed bodies in which they were wanting. But, fuppofing the utmoft in favour of thefe gan- ghd of the fifth pair: the nervous twigs on which they have been obferved are chiefly diftributed to the falivary and mucous glands, about the tongue, jaw, palate, throat, and nofirils, and therefore may be fuppofed to have fome ufe in glandular fecretion ; for we fee the glandular parts in the abdomen are fupplied by the intercojials as well as the mufcular fibres of the heart and intefiines. 2. It has likewife been objected that the inter co - flah fend fome branches to parts under the controui of the will as the pharynx and diaphragm ; as well as to the heart and intefiines, not fubjed to that con- troui. It is well known that the pharynx has its mod confiderable fupply of nerves, from the eighth pair: and the diaphragm is rendered paralytic by tying or cutting the phrenic nerves diftributed to it, which fhews that its motions have very little if any depen- dance on the minute filaments, which it receives from the intercojials . The motions however of both thefe parts are properly fpeaking of the mixed kind, fometimes being voluntary , at other times involuntary : thus the diaphragm moves when we are afleep, as well as when we wake, and continues for fome time, even during a profound apopledic fit : and though we can raife the pharynx by an effort of the will, yet in the adion of deglutition its motions are chiefly involun- tary from the Jtimulus of the food, paffing down the gullet, as has been fhown in the moft ingenious * Haller, El. Phyf. T. IV.. R 2 work. £ * 2 4 1 work of a great and worthy naan lately oeceafed, an ejfay on the vital and involuntary motions oj animals. ? by Dr. Whytt *. ' And it deferves to be remarked, that parts, whofe motions are of this mixed kind, will be found to have generally a double diftribution of nerves, namely fuch as are without ganglions, to fubjeCt them to the will ; and fuch as have ganglions occafionally to iupport thofe motions of the fame parts which go on without the will ; but, thefe lupplies from the interco/tals being very minute, their adtion is generally called forth and aflifted by fome degree of uneafy fenfation or flimulus. If thefe anatomical objections have not force enough to overthrow our dodtrine, the following of a phyfio- logical nature, it is prefumed, will not be more formi- dable. 3. It has been objected, that if -the ganglia inter- cept the communication between the fenforium com- viune and thofe parts whofe nerves are derived from them, they ought not only to intercept the commands of the will, and render the motion of thefe parts not voluntary, but they ought alfo to prevent the im- preflions made on the nerves of thefe parts from being conveyed to the fenforium commune , 1. e. thefe parts ought to be infenfible.. The contrary of which is true , for example, the inteftines, whofe nerves come from ganglia , are among the moft fenfible parts of the body. And if the uneafy fenfation in the lungs, in aflhmatic cafes, was not conveyed to the fenforiuin commune , how could the will redouble the action of £he diaphragm and the intevcojlal mufcle.s ? * P. Z To [ I25 ] To this I anfwer, that the interruption of the par- allel diredtion of the nervous filaments, which pro- bably takes place in ganglions , may intercept the efforts of the will, and alfo render the fenfations of parts wholly fupplied with nerves from ganglions , more indeterminate and confufed than in other parts ; which in fadt is the kind of fenlation proper to thele parts, yet without rendering fuch parts totally in- fenfible, which is well illuftrated by morbid cafes. Paralytic difeafes fhew that the nerves may be fo af- fedted as to become incapable of conveying the com- mands of the will, and yet remain l'ufficiently ca- pable of re-conveying fenfible perceptions. In the palfies which are moft frequent, the parts rendered immoveable by the difeafe have as quick a feeling as thofe that remain moveable by the will, and, what by the way deferves attention, are often moved in- voluntarily, efpecially upon the application of any painful Jlimulus : and it is obfervable that the paraly- tic limbs, which are not to be moved by our volitions, are often called into adtion, when the paralytic perfon is fuddenly thrown into fome vehement pafiion : juft as we obferv.e the fame caufe to produce extraor- dinary commotions in the heart and inteftines, &c. notwithftanding the will, coolly exerted, has no power over thefe parts. Various obfervations fliow that the feelings of parts whofe nerves come from ganglia are by no means acute, but blunt and confuted. We have k on the authority of the great Harvey, confirmed by the ex- periments of Baron Haller, that the heait, though highly irritable, is yet when touched hardly fenfible of it. Dr. Haller afferts that the lungs, liver, fpleen [ 126 ] and kidneys, all fupplied with nerves from the inter- coJtaiSy have been cut in pieces without the animal’s ieeming to feel pain. And what is lefs liable to ex- ception, operations and difeafes in the kidneys, and ulcers in the lungs, fliew their feelings not to be ex- quiiite *. The ftomach, which has a very large portion of the eight pair of nerves bellowed upon it, by ligature* or this nerve, lofes its fallibility and contradive pow- er fo perfectly, that the food neither paffes down the oelophagus, nor is concoded in the ftomach, but, by lpontaneous corruption there, puts on the appearance Of the faeces themfelves in the great inteftines +. This proves what was aliened concerning the eighth pair, 3l ^'ng a fenfory nerve 1 and ’tis in confequence of the fallibility which the ftomach derives by means ot this nerve, as well as its own ftrudure, that the ftomach becomes the principal feat of hunger- “ And (t0 ll,c the words of Dr. Whytt ±1 as ft is " ade'-ced with a mere difagreeable fenfation, when “ we h ave wanted food for any confiderable time, than “ t!ie gu ts, lo like wife it is more fenlible of an ao-ree- “ ?ble feebnS fr°m Sratefui fo°d. and in thefe refpeds ‘ J5. "lay ;’e laid to be more fenfible than the inte- “ irics' Baron Haller has obferved that parts which have nerves from ganglions are not fo diftindly pain- „ u ! as ol"ers> ‘‘ ut anima non adeo accurate locum do.entem diftinguat, fed obiter utcunque, et cutn a!,claa latitudine §.» And this confuted indeter- * • Irritab* et Whytt. Path. Eflays. t bee Vieuflens, Bruni, Morgagni, Haller.. 1 t atn. .Lfl. p. 135. S El™- %f. T. IV. p. 407. min ate [ .127 ] minate fenfation is the fenfation proper to the inte- rnes, though in many inftances they are the feat of exquifite pain ; yet, in confequence of the con- courfe and commixture of the nervous filaments in ganglia , any painful difeafe feated in the inteftines, or in others of the vifeera contained in the abdomen » is lefs determinable to its particular feat, or rather is more apt to affect the parts contained in the ab- domen, not primarily affe&ed, than difeafes of a painful nature, which are feated in the ftomach itfelf, or other parts whofe nerves are unfupplied with gan- glions. And this leads to a natural folution of the caufe of that fympathy, that communion of fenfation, or imputation of fenfation, which fo frequently takes place, in the difeafes of the contained parts of the abdomen, from which fome writers (Linn. *) have very conclufively argued for the nece fifty of fuch a communication of the nervous filaments in ganglia as we contend for, from the bed anatomical autho- rity, and which appears to have fuch important ufes in the animal eeconomy, and to be the occafion of that fympathy or confufion of fintalion among the abdominal vifeera in particular y. * In Haller. El. Phyf. T. IV. p. f The folution of the problems concerning the fympathetick afFedtions, or content of parts, has employed the hands and pens of many ingenious, writers ; and if all the queftions relating to it were difeufled, volumes might be filled, and the fubjedt neither exhaufted nor underfto'od. The ingenious Dr. Whyte has with great acutenefs (hewn that fympathy in general is only to be ac- counted for from a fentient principle, feated in the fenforium commune , where all nerves begin, and communicate; his objec- tions to particular fympathics arifing from a connexion of nerves in ganglions feem inconclufive ; for he remarks that fuch a communication as is fu.ppofed in ganglia to occafion fympathy. C 128 1 4. It is objected alfo that every voluntary mufcfe' in the body becomes involuntary when it is drongly dimulated, for example the accelerators urine? are quite voluntary in their adion ot expelling the urine, but adl involuntarily in expelling the femen. When we condder the date of the foul and body under any great commotion of mind, we find the ufual operations of the mind itfelf are not only inter- rupted, but thofe parts of the body too which the will cannot controul are now agitated by the dorm; for every one has experienced that the heart and 'vifcera in general are vehemently affeded by ftrong. paflions. The mind is in its turn re-aded upon, by very drong bodily fenfations; it being-well known that mufcular parts, which are ordinarily fubjed to our volitions, ceafe to be fo if any part is dimulated by exquidtely pleading, or excedively painful fenfa- tions ; under fuch a ftimuhs , they are neceffarily contraded or convulfed. But it is not therefore to be concluded that the gentle Jlimulus of the blood on the furface of the heart, and of the air, food, and in- tedinal juices on the intedines, of which the mind has no confcious perception at all, much lefs a difa- greeable one, can lay it under any dmilar necefdty, as fome have argued ; and therefore the independence would caufe aconfufion in our fenfations as well as in the mo- tions of our mufcles. — with refpedt to fenfation I have remarked that confufion or indeterminate fenfation, is that, which is pro- per to parts whofe nerves arife from ganglions — and that the muf- cular motions of thefe parts are by means of ganglions not regulated by the will, but fubfift by the application of an irri- tating caufe: and, inftead of proving that fympathy in the abdo- minal vifcera does not arife from ganglions, they prove that it does, bee Whytt ondifeafes of the nerves. [ 129 3 of thefe motions on our minds, cannot be explained from this analogy, which does not fubfift in faCt. This objection therefore can have no force againft our doCtrine, however it may recoil upon another ; as all voluntary mufcles whatever may be excited to contractions by irritations exceftively painful or plea- fing, the contraction in fuch cafes being involuntary, neceffary, and uncontroulable. But the ftimuli that affeCt the heart and other parts, whole motions are naturally involuntary, are not of this clafs and ftrength, and indeed are fo little perceived by the mind, as to lay it under no fuch neceffity, as* that Jlimulus which renders the action of the acceleratores urince involun- tary in expelling the femen. 5. Laftly it has been objected, that, though the motions of the uvea are involuntary from light af- feCting the eye; they are truly voluntary when it contracts in order to the diftinCt vifion of an objeCt placed near the eye, whofe minute parts we want to obferve accurately. It leems on the contrary certain, that the contrac- tions of the uvea , in order to diftinCt vifion, equally arife from different impreffions of light on the retina > and are equally involuntary, and folely dependant upon the impreffions of different degrees of light in all cafes: the diftinCtion indeed is chiefly verbal; as it is granted, that the motions of the uvea are in- voluntary from light affeCting the eye, that is, differ- ent degrees of light (hiking upon the retina necefla- rily occafion more or lets of contraction in the pupil. But as vifion, confidered as diftinCt or indiftinCt, is occafioned by various impreffions of light upon the retina, the contraction of the pupil neceffarily fol- Vol. LVII. S lows. : ... C ^30 ] lows, according to the degree of that impreflion : in the cafe of diftant objects, the faint impreffions of light on the retina make the pupil contract little, and it remains wide; for dilatation is the natural Hate of the pupil. In obferving very near objects, the light is cceteris panbus Hronger, and ftimulates the retina , and contracts the pupil more. In a word, the contractions of the uvea arife from the fenfations of the retina involuntarily and uniform- ly, according to an invariable law and connexion; otherwife why does the pupil conftantly become immoveable, when -by a gutta ferena the retina be- comes inlenfible ? Let any one obferve the motions of the pupil, by the help of a mirror, they will al- ways find it impracticable to fubjeCt them to the will. Indeed it is clear from experiments, as well as difeafes, that the iris , like all other parts provided with nerves from ganglia , has but a dull degree of feeling, and is moved entirely independent of the will*. << What perfuades me, fays M. de Haller, “ that the iris is much lefs fenfible than the retina, is, that if, after having pierced the cornea , you ir- “ ritate or cut the ins , it is not therefore contracted, “ whereas the lead increafe of light makes it con- “ traCt ; which evidently proves that this contraction “ d°5s not depend upon the proper fenfibility of the “ ins, but on that of the retina . The gutta ferena ferves to prove the fame thing, the iris being no dc : \Jc. Sin diftantia d adhuc minor fuerit, Problema evadet impoffibile. • • ; V . ‘ ’ r : f f - J '• prop., it.: Iifdem pofitis, invenire locum in quo vires corpo- ! rum fint ad invicem in ratione data. Sit ratio data h ad c , in qua oportet efie vim cor- poris majoris ad vim minoris. Secetur produda SC (Fig. 2.) in E et P, ita ut fint SE ad EC, et SP ad PC in lubduplicata ratione ipfius s ad h ; et locus quaefitus erit fuperficies Iphaeras PFE, diametro PE defcriptae. Q^E. I. Demonftratur ut Prob. I.’. Corol. i. Si fecetur CS in G, ita ut fit CG ad GS, ut — - — ad ES, pundum G erit centrum ad quod dirigetur compofita gravitatio infuperficie PFE. Jungantur FS, FG, FCj et agatur reda GK ipfi SF parallela. Cum ratio CG ad GS, five CK ad KF, componatur ex rationibus CK ad KG, (id eft, CF ad FS, five CE ad ES) et KG ad KF ; et, per conftrudionem, ratio CG ad GS componitur ex rati- onibus CE ad ES, et h ad c confequens eft, quod KG [ 136 ] KG eft ad KF ut /j ad c-, id eft, ut vis corporis S agens fecundum redam ipfi KG parallelam, ad vim corporis C agentem fecundum redam FK. Corol. 2. Et, ft in diagonali FG fumatur FH =r FC, et agatur H M ipfi SF parallela, vis compoftta in pundo F erit reciproce ut redangulum GFM. Demonftratur ut Corol. 4. Prob. I. Eadem intelligenda funt de fuperficie interiori pfe, . et pundis g, k, h, ?n, in Fig. 3. Corol. 3. Ubi h minor eft quam c, centrum^ verfatur intra fuperficicm pfe, ut in Fig. 3. Ubi major, centrum G verfatur extra fuperficiem PFE j eoque ; longius diftabit a corpore C, caeteris manen- tibus, quo- major fuerit rat o data. Caeterum (ut id obiter moneam), vires conjundas gravitatis non in diverfis ejufdem fuperficiei partibus tantum, fed. et in diverfts fuperficiebus, funt inter fe in ratione fupradida. V. gr. Gravitas in pundo F . eft ad gravitates in pundo /, ut redangulum Cf m ad redangulum CFM; in Figg. 2. et 3. $ C H O L. Si ratio data eadem fit ac s ad c, fphaerica fuper- ficies PFE in planam mutabiturj haud fecus ac in : Schol. 2. -Prob. I. pundo P in infinitum abeunte. Si ratio fuerit major, pundum P cadet in contrarian* partem centri S j et fuperficies iterum erit fphaerica, ar corpori inajori eccentrica > tjufque diameter inve- nitur C r37 ] ^itur^ut fupra. Sin ratio data fuerit major quam b -|~ dL x s ad Pc; vel minor quam kzs ad k ~\-dz x c i Problemaerit impollibile. PROB. III. Corpufculorum, conjundtis corporum S et C viri- bus attradlorum, motus generatim defcribere. Si corpora S et C medio fluido circumdentur, in quo mergantur corpufcula Ipecifice leviora aut gra- viora quam iftu.d medium, corpufcula ilia perinde afcendent vel defcendent, per utriufque corporis at- tradtionem, ac fi ad corpus unicum traherentur; ideoque movebuntur vel in redtis lineis vel curvis, prout eorum motus diredti lint vel obliqui, refpedtu. centri compolitae gravitationis. Nam centrum hoc idem valet * ac corporis unici centrum in eodem pundto locatum. Cas. I. Corpufcula inter corpora C et S in redta CS lata, quae Ipecifice leviora funt medio ambiente, tendunt ad pundtum A, Fig. i . Nam qua; inter cor- pus C et puudtum A fita funt, afcendunt a corpore C ; et quae inter corpus S et idem pundtum, a corpore S afcendunt, (per Schol. I. Prob. I.) Corpufculum autem in ipfiffimo pundto A litum, in cequilibrio de- tentum, requiefcit. Qua; in redta CO lira funt, ex altera parte corporis C, afcendunt ultra limitem O ad altitudinem indefinitam. PPec enirn, in toto itinere, quantumvis longo, afcendunt fimul ab utroque cor- pore C et S. Contra lieret, in corpufculis ipecifice gravioribus : quod et de cafu fcquente dicendum. , ■ j « i • • « -f » * H?ec mathematice dicSla funt, non phyfice. Nam centra minime trahunt. Vol. L VII. T Cas, II. [ 1 38 ] Cas. II. Omnia corpufcula leviora, e corpore C oriunda, iis quag in reda iyzygiarum PS fita font ex- ceptis, afcendunt in curvilineis femitis, non multum diffimilibus, quantum auguror, eis quae pundis fig- nantur, in Fig. 4. quarum convexitas obvertitur cor- pori anajori S, et quae magis magifque tendunt verfus plagam ei oppofitam. Leviora enim, quae in fuper- ficie limitante OLA fita funt, afcendunt a pundo A ; et quae in fuperficie PFE, vel p fey (Figg. 2. et 3.) a pundo G, vel g; quoniam haec punda funt centra gravitationis compofitae, ad corpora C et S; per Co- ro). 3. Prcb. I. et Coro). 1. Prob. II. Ejufmodi cor- pufcula, cum primum expedita funt a corpore C, al- cendunt quaquaverfum ab ipfius centro, faltem quam proxime ; peragrando autem fuperficies p f ey PFE, &c. afcendunt quafi depul fa a centro g> vel G, &c. quod femper jacet inter punda C et S j et, dum au- getur ratio h ad cy manente difiantia CS, perpetuo re- cedit a corpore C j per Coro). 3. Prob. II. et citius, auda quoque difiantia CS. Quamdiu intra fphaeram limitantem comprehenduntur, afcendunt fere a cor- pore C. In tranfitu enim per fupeificiem interiorem pfe, fugantur a centro g, quod inter C et e loca- tur j at, ob compofitionem motus antea acquifiti cum nifu afcensus a centro gy dirediones in quibus affur- gunt, feu tangentes femitas fuae, fecant redam Cg in pundis quae adhuc propiora funt corpori C quam eft pundum g. Egrelfis extra fphaeram limitantem, et fuperficies exteriores PFE permeantibus, afcenfus eo- rum magis magifque fit a corpore S. Fugantur nunc a centro G, quod locatur inter E et S j eoque magis appropinquat, casteris paribus, corpori S, quo altius afcenderunt corpufcula a corpore C. 6 Corol. [ *39 ] Corol. i. Corpufcula, quae a corpore C prope rcc- tam fyzygiarum CS aflurgunt, obi regiones ipfi A vi- cinas attigerunt, fefe ad latera diftimdent, curfumque in partes contrarias fledtent j velut aqua fontis arte fa- bricate fimul ac fummam confecuta eft altitudinem, quaquaverfum diffluit, retrorfus jamjam itura. Et omnium quidem femitis corpufculorum ex toto cor- poris C hemifphaerio ipfi S proximo fufcitatorum corn- petit vertex V, Fig. 4. feu pun&um ex quo curva in contrarium producitur. Cis hunc verticem, corpuf- ctila ad corpus S accedunt ; trans, ab ipfo recedunt. Qg® ab hemifphasrio oppoftto ortum ducunt, ab ipfo S nunquam non recedunt. Corol. 2. Recedentibus corpufculis a corpore S, id eft, trans verticem V, angulus RTC, (Fig. 4.) fub femitas tangente RT et fyzygiarum redta CS conten- tus perpetim minuiturj ad modum parabola?. Corol, 3. Vis, qua corpufcula leviora in his fu- perficiebus fphsricis fita afcendunt, eo major eft quo propiora funt ilia plagas oppofitionis, pOP. Manen- tibus enim medii ambientis et corporis immerfi den- iitatibus, ft augeatur vis acceleratrix gravitatis in qua- cunque ratione, augebitur in eadem ratione differentia gravitatum fpeciftcarum, id eft, vis qua corpus im- merfum lurfum vel deorfum fertur in ifto medio. Augetur autem vis acceleratrix in unaquaque harum fuperficierum, pergendo a conjunctione CK per F ad oppofttionem CP ; -f* per Corol. 4. Prob. I. et Corol. 2. Prob. II. f Vis acceleratrix augetur in fuperficie quacunque EFP, ab E ad F et P, quamdiu ratio data in Prob. II. minor fuerit quam v't ad 1, pofita r=r. Si verb hre rationes aequentur, vires in E et P erunt, non accurate quidem fed quam proxime, sequales. Id quod ex Corol-. 2. Prob. II. facile colligitur. T 2 PROB. \ C H° ] P R O B. IV. Ex fupradidis, praecipua caudarum cometicaium phenomena derivare, in theoria Newtoni. Secundum hunc Philofophum celeberrimum, cau- dal cometicae ad hunc modum formantur: “ * Cau- “ das a capitibus oriri et in regiones a foie aveifas af- “ cendere, confirmatur ex legibus quas obfervant. f Sufpicor afcenfum ilium ex rarefadione materia; l*ve 1 __ T . Porro, poiita lolis parallaxi media 87/, 68 (ut ex nupero veneris fub foie tranfitu collegit vir rerum aftronomicorum peritiffimus Jacobus Short, S. R.S.) femidiameter terrae eft 4,2; ejuique materia -3-^7?-?? pars materiae folis ; ut meus profert calculus. Quo- circa, denfitas terrae eft ad denfitatem cometae, ut 1 ad : — ; id eft, ut 1 ad 4, 2 cub. x 342686 i,ycub. X 1510724 44. Hie igitur cometa, qui in perihelio fuo quail decuplo propius quam terra ad folem accedebat, 3 4 fere vicibus denfitate terrain fuperabat. Veruntamen, hos nolim venditare numeros tan- quam perfeftos, et cometae hujus denfitatem abfolute exhibentes. Inftituto meo fufticit, fi, dum calculi methodum illuftrant, non longe a vero aberrent; • lum mam- enim accurationem ab ipfa Hevelii obfer- vatione haud efte petendam, palam eft. Probabile omnino videtur, quod oblervator illuftris magnitudi- fiem capitis aeftimarit fecundum redtam axi caudae ■ normalem,, quippe in ea fola diredtione dimetiri po~ ttiit caput ablque cauda ; et capillitii latitudo, de qua hie agitur, nempe verfus folem, paulo minor fuerit quam dimidium iftius magnitudinis. Haec fuppofitio non male quadrat cum ultima oblervatione hujus co- metae, quam Plevelius habuit die 20° Apriiis. Po tempore diftantia cometae a lole, meo computo, erat 24237; et a terra, 89602. Jam, apparens latitudo capil- * [ J49 ] capillitii verfus folem eft ut diftantia comets a foie diredte, per Corol. i. Prob. V. et ut diftantia a terra inverfe ; id eft, ut 44*44 ad 44444, five ut 4 ad 1 . Quare, ft in priore obiervatione iuiii'et 3', m pofteriore eftfet 45" j et capillitium emineret luper nucleum 40" circiter; quod quidem non adeo sgre, adhibito perfpicillo, perceptu foret. At teftatur Hevelius, quod “ die 20° Aprilis, cum a nobis ultimum obfer- “ varetur cometa, in frontifpicio capitis materia ilia £C dilutior jam adeo erat contradta, attenuate et difti- ** pata, ut parum admodum amplius fupereftet 3 ad “ utrumque latus vero fatis dilatata extitit.” Cre- dibile igitur eft, latitudinem anteriorem capillitii, etiam in prima obiervatione, minorem extitiffe quam latera- lem j i.e. minorem quam 3'. Quod ft haec latitudo minor fuerit quam 3 , minuenda erit materia comets, ejufque denfttas, in duplicata ratione, quam proxime; per Corol. 2. et 3. Prob. V. Plujus ergo comets denfttas non major eft; quam quae fupra deftnita eft; fed poteft efte aliquanto minor. Qusrebam itidem denfttatem cometa? anni 16 82. «* Aug. 20. St. V. diameter capillitii axi caudae per «« nucleum normalis, menfurante Flamftedio, erat “ 2,' o" -} cujus diftantiae ipfe nucleus vix _4 aequabatj “ ideoque latus erat circa 12 V' file iterum necefte habemus fumere dimidium diametri capillitii pro la- titudine ejus verfus folem 3 quanquam vjx dubium eft quin haec aliquantulo minor fuerit illo. Et in hac fuppofttione, iifdem calculi veftigiis inliftendo, inveni denfttatem terras. efte ad denfttatem comets ut 1 ad o, 45623 feu ut 1 1 ad 5 circiter. Notatu non indignarn arbitror aliam hujus comets obfervationem a Flamftedio fadtam die 4 Septemb. quo C is° 1 quo tempore erat {c nucleus limbo capillitii vicinioi “ quatn antea [20 Aug.] duplo ieie. Supra mon- ftratum eft, quod capillitii latitudo apparens verfus folem eft ut diftantia a foie direde, et a terra inverfe ; ex quo, computum ineundo, invenio capillitii latitu- dinem die 4 Septemb. efle ad iplius latitudinem 20 Aug. ut 1 ad 2, 1542. Quod cum obfervatis probe congruit; ut conferenti liquebit. Fatendum tamen, maximam hujus differentiae partem fecundae illaiuni rationum deberi. Vellem fane plura adducere exempla, caeterofque cometas, ratione denlitatis, inter le conferred fed ob- iervationum penuria impedimento fuit quo minus aliorum denfitates ad calculum revocaverim; nullae cnim extant, quas mihi quidem videre contigit, adeo fubtiles ut huic dilquifitioni apte infervire queant. Nec mirum 3 quum admodum difficile eft, arcus tana exduos ad amuflim mentiri. Quantum ex allatis conjedura aftequi poflurn, eadem hie valet regula quam obtinere demonftravit Newtonus in planetis, tc eos nenape denliores eft'e, caeteris paribus, qui funt “ foli propiores Infuper colligere videor, quod ficut cometoe ut plurimum ejufdem fere funt magni- tudinis cum planetis, ita non rnulto plus diferepant cometae a planetis quoad denfitatem quam planets diffident inter fe. Nam terra, per Newtoni demon- 11 rata, lextuplo denfior eft quam faturnus. Quin- etiana, quod cum diftantiae periheliae funt aequales, .eometae planetis rariores funt; — in hunc foitalle fi- * Secundum fuperiorem calculum, cometa anni 1665 erat < quail 7 2 vicibus .deniior quam comcta anni 1682. tor uni au- tem diftantiae periheiise, Halleio computante, crant 10649, ct 58328. nur. [ ISI ] nem, ut in tranfitu prope planetas, minus turbent eorum motus ; et ut, eidem gradui caloris objedi, facilius vapores emittant, ad formandas caudas. Sed manum de tabula j neque enim conjedandi licenti® indulgendum. Si in pofterum aftronomi ob- fervationes hujufmodi inftituerint, ea fedulitate qua phaenomenis ftellarum tam fixarum quam errantium invigilare folent, certiorem tandem penitioremque fi- derum caudatorum cognitionem fperare licebit. P. s. EST et infra fuperficiem comet® limes attradionis, intra quern vis folis fortior eft quam comet®. Hujus inveftigatio pendet a diverfa gr.avitatis lege, crefcentis fcil. in fimplici ratione diftanti® a centro j per Prop. 73. Lib. I. Newt. Princip. ejufque natura eft, quod ft a quovis ipfius pundo / (Fig. 6.) ducantur red® ad centrum folis S et comet® C, quadratum prioris in pofteriorem dudum, S/^x/C, efficiet folidum da- tum ; quod eandem quidem habebit rationem ad cu- bum femidiametri comet®, CN, quam habet mate^ ria in foie ad materiam in cometa. Verum, cum hujus limitis diameter perexigua eft refpedu diftan- ti® a foie, et propterea omnes red® S /, ideoque et / C, funt quam proxime ®quales, h®c fuperficies l 111 parum differet a fph®rica ; ejufque diameter ei it re- ciproce ut quadratum diftanti® comet® a foie. Sed h®c, aiiaque ad hunc cafum fpedantia, Prob. II. con~ fimilia, mathematic® duntaxat funt contemplation^ ; eoque confulto in fuperioribus pr®termiftmus, utpote ab argumento noftro alien® ADDENDA, [ 153 ] ADDENDA. I. Afcenfum caudae cometicas, quern ope cujufdem. medii cceleftis perfpicaciffimus Newtonus explicatum dedit, aliquantulum illuftrare aggrefii fumus. Quas- nam vero fit iftius medii natura, quifve terminus, magna quaeftio eft, et tenebris involuta. Diverfts nominibus illud Newtonus infignivit, fcilicet auras asthereae, materias ctelorum, et atmofphaeras*. Alirs in locis fummus philofophus afferuit, et variis iiique graviffimis rationibus afiertum ftabilivit, “ cceIos re- « fiftentia deftitui ” ; quo pofito, h$c aura aetherea non poteft efte non rariflimaj et materia ccelorum ni- hil aliud quam vapores longe tenuiftimi. Corpus folis ingenti atmofphaerae pondere premi, non delunt argumenta quae nobis fidem faciant ; et ex macula- rum folarium phaenomenis certum eft, earn, una cum corpore folis, circa axem fpatio 254. dierum ro- tari. Qupd ft hae maculae triduo diutius pone foiem latent quam fefe nobis confpiciendos praebent, ut a quibufdam obfervatum eft, necefle eft altae lint lupra l'olis fuperficiem parte -J.T -f* diametri folaris ; et ad hanc minimum altitudinem porrigi folis atmol- * Vide periochen citatam Tub Prob. IV. in qua Au£tor lias voces promifcue ufurpafle videtur ; faltem non piaecife inter eas diftinxit. f Wolfius in Aftron. macularum folarium altitudinem multo majorem juflo reftimavit, fcil. 33+ diametri folis : manitefto er- rore; ponendo finum verfum i-o graduum aequalem 15 centeii- mis partibus radii, cum revera fit aequalis tantum 15 millefimis. 2 - phasrano, [ *53 ] phaeram, par eft credere. Cometa anni 1680 in pe- rihelio minus diftabat a foie quam parte fexta diame- tri folis j et in vicinia ilia, ex audtoris clarifiimi fen- tentia refiftentiam nonnullam fentire debuit. Sed quas fit illius atmofphasras altitudo, hucufque incom- pertum eft. Veriftmile videtur, earn intra modicos terminos contineri. Etenim, ft ad orbes planetarum pertingeret, caudas cometicas per eos tranfeuntes, impulfu illius gyrantis tanquam vento validifiimo rap- tae, ab occafu in ortum detorquerentur. Atqui me- dium, de quo quaeftio eft, eoufque extendi oportet, quo cauda cometre cujufvis pullulare incepit. Hie locus orbibus mercurii et veneris, immo et ipfius terras “f-, fuperior eft. Tam immanis autem ampli- tude atmofphaeras folis concedi nequit. Quid de re tarn obfeura ftatuendum fit, incertus haereo; hasc tantum rata habens, medium hocce te- nuiftimum efte, et quam facillime rarefeere; paulo autem denftus efte prope folem quam ulterius, ter- minumque ejus extra fphasram orbis magni efte lo- candum j item, non modo non rotatum vertigine quali corpus folis, fed et fumme quietum efte ac tranquillum. Denique, non abftmile videtur, cau- darum materiam longe magis volatilem efte quam exhalationes e corporibus quibuflibet terrenis aut planetaribus elicitas. II. Quibus uftbus inferviant cometarum caudas, id eft alia quaeftio, explicatu difficillima. Ccnfuit Newto- '* Princip. p. 525. f Conflat ex phaenomenis cometae anni 1680. Alii cometae hunc terminum ad erbem ufque martis, aut fupra, forfan smove- ant. Sed hoc non exploravi. Vol.LVII. X mis . [ *54 ] us “ eas * ad confervationem marium et humorum. « ia planetis requiri, ex quibus in planetas attraftis ct et cum eoru'm atmofphaeris mixtis, quicquid li- « quoris per vegetationem et putrefa&ionem confu- tc mitur, et in terram aridam convertitur, continuo “ fuppleri et refici poffit Verum cum, ipfo judi- ce “ perexigua quantitas aeris et vaporum ad om- <£ nia caudarum, etiamfi fpatia immenfa occupantium, “ phenomena fufficiat”; et cum hujus quantitatis perexiguae perexigua tantum pars in unumquem- que planetam incidere queat (ni mea fallat opinio in Schol. 2. Prob. IV. prolata), ambigi poteft an hie fit e praecipuis cometarum finibus. Sed nihil ftatuo. Aliorum efto judicium. * Princip. p. 515. t P* 5*3* XVI, Some iris's lit {invar1 far/ a/W/r, 1/ t// u/d tjf Satyr,! hiZoj Tj'atw. Vol. IYH. TAB . JX . p . 15 j % TI'jkst . T/u>73m/ of V> mM-Baat! 0^ / o^o {W‘ T/e D/ffiai/ty tf'tia/vfafaru/ taf/e Siam ml oai/i/ty outof£h& Am/ , of if earo fo Aa/Oticcm fac rtaoo/i' tf t/i-c moo/ /out font infry/natir/o nfauc/oiPtofaona/ received-, & t/u. fiittjf ia/tot of/iio fa/ia/t/cinp /uo oftnion conccr/u/ia a froftr aiion/anc^fr'tfie Tfiott S £?///&. Jiutiotio rt/iorto m/io/ 6c ttuti/y reco/ioi/cd Ay Jiffoot/iy, faatJo/nc S/fo miyAttiouAfa it very ooom &Jo reaefu fai/iya/ra, tocec fens etaa/*! nr/toPMO ofao/t) fa/ /ui'oAny more /mffair ami fa /vondj miy/it not to at fa to accomf/ioA faic/aonctfiofooict’ tn ay teat rnaai/y tieyyo. jVojiTb: rfua&diyurrv dvltwtr Cttm-m-Jt-Berada^. ffn/mono/, Jlfonffay faountry fo t/ioeaotofit. Jii/oerJfiocr/g, ^ l to rocvras oydXoyziv cci'aroXtxorapa./' avrqv etvcu ro/y xariycLpcov.T. G.Z.l. c . 15. \V^_L faionfofai/z fatty ott/ur/tfa q t/y *to fat toot of ^ta/ftyo/'o, or 3 tty faoft/ijto/ut f?vm, itr. 4: f C jss ] Received February 6, 1767; XVII. Some Attempts to afcertain the utmojl Extent of the Knowledge of the Ancients in the Eaft Indies : by Mr. John Caverhill. ReadMarch x9, A L L the moderns who have treated / * # XJL of the geography of the ancients, more particularly in their account of the Sinai, the moft oriental country they were acquainted with, have differed fo widely from the only guides they had to follow to the eaft of the Ganges, that I have undertaken to lay before the Royal fociety fome obfer- vations, which may contribute to determine, with greater precifion, the fixation and limits of this country. But as geographers have been unanimous in fup- pofing the Aurea Cherfonefus to have been the fame as the prefent kingdom of Malacca ; the only diffi- culty, which remains, is to difcover how far they failed beyond it, in the days of Ptolemy. And, that the proofs alledged in fupport of what may be af- ferted in the courfe of this difquifition may be better underftood ; I have thought it neceflary to annex a correft modern chart of this Peninfula, and have alfo added the outlines of Ptolemy’s, (See Tab. vm. ix. x.) for reafons which will foon appear. It may be proper firft to obferve, that Cattigara was the name of a port fituated fomewhere beyond X 2 the [ ri6- ] the Aurea Cherfonefus or Malacca ; and that the antients had never failed farther than Cattigara : for contiguous to it was a terra incognita a. But at what difiance the Aurea Cherfonefus was from Cattigara, Ptolemy himfelr was ignorant ; for he fays, “ that Marinus, who is quoted by him upon- “ this occafion, had not marked the number of the “ fladia : tu A uno ry\g xgvryg i enevQev evuvjiuv eivcu ie ry kcu rovg TrXsovjag Txra.^ cwlvjv ev yjfxt^ug te eiKotri auTuXu^uveiv vsoXiv 'Z.u&ctg. utto A tuv 7Lu£mv “ gzrpog votov 3iv xaXcuy,evov il Xcijv^uv axgcu-. Atto $e tod tuv ** KoXTrog psytg-oc, xuXovpivog Xivcov KoX7rog. 1 &Tog “ ptXi/ [A,t “ *a, JV I V$l- og avctloKriv ytftuv Tv\g otKCuysvvjg, vtt t( uvjov #vs%cyrc4 T0V yhtov, KdXovysvv] %(>vn, appears to have been the kingdom of Laos. This will ftili be more probable when we conlider that no country immediately to the call or weft of it, viz. Pegu, Siam, or Cochin- China, are famed for thefe manufactories, “ P. M. E. ubi fupra. “ in [ i69 ] “ *n Holland ; befides, the inhabitants are the moft fubtle merchants in the eaft, and the country itfelf “ is fuperiour in fertility to moft of thole which “ furround it « ” We are told “ that this city was difficult of accefs, “ and that but a few people were acquainted with “ the courfe in this voyage, and that thefe fewfeldom ** *~aded far : & Tyv 3-ivct Tavfov ou k e aar avjyg Tins ou tztoAAc* ewov- c*)7ro(p(x,lovs, Kci?*.ovyevovg Msn/;o- “ Xag h.” fame fignification, it would sppear that both the name of the ifland and that of the grain were exported from that country. Hyde’s, Hiftor. Relig. Vet. Perf. kc. { Ibidem. s The Celebes is infefted with numbers of mifchicvous and dangerous great monkeys, which keep in bodies too hard for any wild beads to lwirt them, and are only afraid of ferpents, which puriue them to the very tops of the trees, and devour them. Bowen’s Geogr. -Diet. v. ii. p. 378. h The Manillas are original names, and were called fo by the inhabitants before the Spaniards took poueflion of them. Argcn- fol, Hiftor. Z 2 l Not with- C r71 2 3 Notwithd nd’ng Ptolemy bus mentioned the Phi- lippines ; yet we don't imagine that any of the per- fons from whom heacqiii od his information had ever been there: but that they had heard of thcie places at Java (to which they might eafiiy have tailed), either from the Javanefe thcmlelves, or from the in- habitants of the circumjacent ifl mds, who reforted to Java for the fame advantages of commerce which they themfelves came in purfuit of \ However, although they muff almoft necedarily have been acquainted with Sumatra, yet it is evident they had never failed quite round it; for, if they had, they would certainly not have mentioned Ceylon as the larged illand in the ocean k. From hence it would appear that they only knew part of Sumatra and Java ; and either conjectured thefe were iflands, or depended upon fome informa- tions they might probably have received from the in- habitants of thefe places, relative to this particular. So that here we may venture to fix the limits of Ptolemy’s knowledge; for, as thefe idands at that time were but a late difeovery, they were very im- perfectly known ; and unfortunately the geographers, who lived after him, were all fo prepofTeded with his fuperior abilities, that they imagined his accuracy would bear no correction, and that he had exhauft- ed the fubject. For no other author mentions any difeoveries to the ead of thefe, taken notice of by him; 1 The diftance between Malacca and Java was lefs than be- tween Malacca and Cattigara ; befides, the fouth weft monfoon was a fairer wind to the firft than the laft place, and of confe- quence this voyage muft have been much {horter. k Agathem. 1. ii. c. c. 8. 3 and 073 ] and Marcianus Heracleota had fuch an opinion of his great merit, as to call him by the name “ of the <£ mod divine and mod wife Ptolemy ; m yscoTgp- tc (plO£$ TCU SsiOTciJoU KUt aroQuTujov IT TO?\ZfJLcLlOV,” By a retrofpedt on fuch authors as have been quo- ted, and forne others who wrote nearly- at the fame time, according to the order in which they lived, this fubjedt will dill appear in a clearer light. In the days of Strabo, who lived before the Chri- dian tera, and is fuppofed1 to have furvived it 28 years, few people had failed fo far as the Ganges, “ (nrcLvioi \jliv xa>i '&i7rXsuKcco7roXii and ©ttvai by Ptolemy, lib. i. c. 17. Qeivou by Marcianus Heracleota, p. 14. 0^, acervus, cumulus, coll is , &c. it might receive this name becaufe it ftands upon amount, ac- cording to Mandefloe, vol. I. p. 331. to fecure it from inun- dations. None of all thefe ancient writers of geography have ever called this country 0nwv but Agathamerus, lib. ii. c. 7. and it would appear he did it by miftakej for its proper name was certainly Metropolis Xivuv, and ©nat was only an accidental one, which it afterwards received to exprefs more figuratively its fituation. \ XVIII. A C *79 ] Received February 12, 1767. XVIII. ^ Computation of the Dijiance of the Sun from the Earth . By S. Horlley, LL.B . ReSior of Saint Mary, Newington, in Surry, i7. i?. & Read March 26, T Offer the following computation, rather as a verification *767’ JL than an amendment of Dr. Stewart’s. The method, in which I have purfued, is different from what is ufed by that great and able geometrician, in his treatife on the diftance of the fun, but founded entirely on the theorems eftablifhed in that and the preceding traces of the fame author. Let TA be a given line. Take Aw, fo that TA may be to A mt as the moon’s accelerating attraction to the earth, to the fun’s mean difturbance of that attraction. Take AG quintuple of Am. Take AP, fuch that twice Aw may be to AP, as TGtoTA. Now it is proved in the twenty-fifth propofition of Dr. Stewart’s fourth trad, that the cube of TA is to the cube of T P, in the duplicate proportion of the periodic month to the anomaliftic month. Therefore the proportion of TA3 to TP3, and confequently that of TA to TP, is given; and by divifion, that of TA to A P is given. Therefore TA being given, A P is given. Now T G : T A — 2 Am : A P. That is, A a 2 TA T A — 5 A m : T A = — TA — 5 A m x A P. C 180 ] 2 A m : A P. Therefore T A X 2 A m r . T AxAH — c A m x A F Therefore 2 Am — ~rr . , ^AffixAP 2 TA-f 5 A P X A m _ ^P 1 hat is 2 A m -] p-^-— > or "Pa — n. 1 . That is, Fig. I. A« = P T A X A P -t- 4- 4- j; 1 zTA+5AP- £ 7)1 G 2. Let TA reprefent the moon’s mean diflance from the earth, n Take TV, fuel} that TA may be to TV, in the duplicate proportion of the periodic month to the fidereal year. Take TG, fuch that VT may Fig. 2. be to TG in the proportion of the moon’s accelerating attraction to the i earth, to the fun’s mean difturbance of that attraction. Take TE, 1 jfuch that TE may be to TA, as TA to TG. Take EO,fuch that the |i rectangle EGA may be equal to 3TE x TA. Upon the centre 1 , with the interval TA, defcribe a circle. Draw O.v perpendicular to AB, , meeting the circle in x. Take A D AT. The proportion of TA | to TV being given, and TA being given, TV is given. But the pro- portion of TV to T G is given. Therefore TG is given, and the proportion of T G to T A is given. T G : T A T A : TE. 'Therefore the proportion of TA to TE is given. Therefore TE is given. Therefore 3TE x TA is given, therefore EO X OA is given. And EA ( T E — T A) is given. Therefore A O is given. But AB ( — 2 AT) is given. Therefore OB is given. Therefore A Ox OB is given, AO X OB ~OV (by the circle). ri here fore 0:0, and confequently O ,v is given. But DB ( =: 3 AT) is given. Therefore the proportion oi DB to O x is given. [ 181 ] And the proportion of D B to O is that of the mean diftance of the fun, to the mean diftance of the moon. ,r This is in brief the method of my computation. The computation is as follows : The periodic month is to the anomaliftic month, as 57600 to 58091. Therefore (in Fig. 1.) TA3 : TP3 = 57600* : 58091* = 3317760000 : 3374564281 = I’0O,2,2748963i5St864i9753o'864i97s3o> &c. Hence, by extrafting the cube root, I find TA : TP - 1 ; 1,005674827053. Therefore put TA~i, Then TP — 1,005674827053 j and A P —0,005674827053" T A x A P Hence — — — = 0,002797722 = Am. 2! A -f- 5AP ' 1 (See Fig. 2). The fquare of the periodic month is to the fquare of the fidereal year, as 1 to 178,725. Therefore TA : TV — 1 : 178,725. But TV : TG = 1 : 0,002797722. Therefore TA : TG zr 1 : 178,725 x 0,002797722 = 1 : 0,50002286445. TA : TG zz 1 E ; TA. Therefore TE : TA rz 1 : 0,50002286445. Therefore put TE — 1. Then TA zz 0,50002286445 And E A = 0,49997713555 And 3TEXTA zz 1,50006859335 = EOA. . EAN Hence AO (=Vte xTA I- E a1 — 1,00003658292. But AB _ 2TA = 1,00004572890 Therefore OB — 0,00000914598 Therefore AO X OB — 0,0000091463145866546616 Therefore v'AOxUH zz 0,00,32024287 = Ox But DB zz 3TA rz 1,500068593 Hsnce DB : O.v zz 496,0073 : 1, Thefc t 182 ] Thefe computations have been made with no fmall rigor. I was fenfible that, to obtain an accurate con- clufion, it was necefiary to determine AO with ex- treme precifion ; and for that purpofe I fubmitted to the laborious tafk of computing the foregoing num- bers to the 1 1 th or r2th decimal place, by the com- mon operations of arithmetic. In the refult I differ from -Dr. Stewart, by much lefs than T_L__.th part of the whole diftance, that is, by lefs than 5 femi- diameters of the earth ; a very contemptible dif- ference in fo nice a calculation. That great mathe- matician indeed fecrns to have flattered himfelf, that he had determined the fun’s diftance within T-rV-s-a-a °f the truth. I fufpedt that when he af- firmed this, he did not confider that to attain fo great an accuracy in the conclufion, the line Ey in his method ( vide Stewart on the fun’s diftance, Fig. 10.), or AO in mine, fliould be determined ftridtly to the nth or 12th decimal place. And after the utmoffc rigor of computation, I am afraid any pretenfions to luch extreme nicety in the refult will be but ill-founded. For it is very likely that thefe computations reprefent the fun’s difiance lefs than it really is : becaufe the whole progrefiion of the moon’s apogee (which is the' bafis of the calcu- lation) is afcribed to the fun’s difiurbance of the moon’s gravitation to the earth. Whereas part of it muft be due to the difiurbances of the planets. What part is due to them we cannot tell, and there- fore cannot allow for it. But in giving the whole to the fun we certainly overrateEis difiurbing force, and by that means muft obtain too fmall a difiance. It [ 183 ] It is mod likely indeed, that the motion of the apo- gee produced by the difturbing forces of the planets bears but a very fmall, perhaps infenfible, proportion to the whole. But thole who are madeis of Dr. Stewart’s theorems will eafily perceive that an infen- fible error in the proportion of the moon’s gravity, and the fun’s didurbance, may produce a very fenfible error in the proportion of tne mean didances. And therefore the real didance is probably greater by two or three femidiameters of the earth than thefe com- putations make it. . This, however, is much too nice a point for the approaching tranfit, or, perhaps, for any method of observation, to determine. The highed expectations aftronomers will be anfwered, if they can come within 50 or 60 femidiameteis of the earth. It is to be hoped, that every civilized nation of the univerfe will give due attention to that inteieft- inp- phenomenon, which we, the prefent ponenors oft hefefublunary regions, (hall behold no more ; and that proper perfons will be fent in due time, and duly equipped, to the mod advantageous dations.^ If the decihons of obfervation in fo nice a point fhpuld be found to agree with the previous conclu- fions of theory, the difciples of Newton will have no fmall reafon to exult in a new attedation of na- ture, to the truth of their great matters dodtrine. But it is much to be widted, that they, who mail be deputed to profecute this curious fearch, in didant and fequedered parts, may dived themfelves of all prejudice ; that they may have nothing at heart, but, that which the world will expedt from them. 7 [ 184. ] the advancement of real fciencej that they may be diligent in their obfervations, and faithful in their reports ; and not facrifice the repofe of their own minds, or the interefts of philofophy, to the ci edit of an admired hypothefis, the memory of a friend, or the jealcufies of rival nations. If the moon’s mean didance from the earth be 60 4- femidiameters of the earth, the funs mean diflance is 30008,4416 femidiameters of the earth. The fun’s femidiameter is to the femidiameter of the earth, as 139,876 to 1. The globe of the funis to the globe of the earth, as 2736718,8 to 1 ; and the fun’s horizontal parallax is 0" 52///,4i5. February 8. To fatisfy myfelf more fully of the accuracy of ifly work, I this day re-computed the whole, from the determination of EA, in Dr. Stewarts approxi- mating method. I found the proportion of DB to vs (fee Dr. Stewart on the diflance of the fun, Fig. 10.), that of 496,00579 to 1 ; and the pro- portion of DB to tv, that of 496,00805 to 1. The mean of thefe two gives the proportion of DB to ox, nearly that of 496,0069 to 1. Which differs from the refult of my former computation by lefs than _ x 4 4 o-t._ of the whole ; and the method of the former computation is undoubtedly the mod ac- curate. Supplement [ *85 3 Supplement to the foregoing Paper. N deducing the diflance of the fun in femidiameters of the earth, and his horizontal parallax, from the proportion above con- cluded between the fun’s mean diflance and that of the moon ; I have fuppofed the latter to be 604. femidiameters of the earth, as it is reckoned by Sir Ifaac Newton. According to the hypothecs which feems to be now generally received, that the denfity of the moon is very nearly equal to that of the earth, (the French reckon it rather lefs), the moon’s mean diflance fhouldbe little more than 60,23207, that is, not quite 604. femidiameters of the earth. But from fome computations that I have formed with great care ; I have reafon to think, that Sir Ifaac Newton’s deter- mination is much nearer to the truth ; that the denfity of the moon is actually greater than that of the earth, in the proportion of 6 to 5 nearly ; and that the moon’s mean diflance amounts to 60,441 femi- diameters of the earth ; which differs from the diflance affigned by Sir Ifaac Newton, by lefs than To4T of the whole. S. Horfley. Read June 19, T 1767. A B b Vol. LVII. Received [ *86 ] Received February 12, 1 767. XIX. Defer iption of an improved Apparatus for performing EleElrical Experiments , in which the EleElrical Power is increafed. , the Operator intirely fecured from receiving any any accidental Shocks , and the whole ren- dered more convenient for Experiments than heretofore : By C. L’Epinafie, F.R.S. Read March 12, I, F* i iHE firfl method of improve- ‘/0/’ ment confifts in lining the in- fide of the glals cylinder or globe with the follow- ing compofition. Take 4 th of Venice turpentine, 1 lb of refin, ilb of bee’s wax; boil thefe over a gentle fire, flirring them now and then, for about* four hours, at the end of wh'idh, ftirr in a quarter of a pound of vermilion : then, a little of the mixture being taken out and left ro cool, will be hard and brittle j a token that it is fit for ufe. Flaying well heated your globe or cylinder, pour the melted mixture into it 3 turn the cylinder about fo as to fpread it evenly over the infide furface to the thicknefs of a fixpence, and let it cool very gradually. The advantages that refult from this are as follow. 1 ft. Upon repeated trials I have condantly found, that a cylinder thus lined a&ed with much greater force I i87 ] force than it did before it was lined, every other cir- cumftance alike. When firft I made this obfervation, it induced me to try what effeCt the lining would have upon fome cylinders, which I had found fo bad that I had laid them afide as ufelefs. Upon being lined, they proved much better than any I ever had of the fame fize before. 2dly, Electrical machines, when laid by for any conliderable time, are very apt to be out of order, and fometimes require much trouble before they can be brought to aCt : this inconvenience is in a great nieafu re removed by thus lining the glafs. 3dly, The cylinders thus lined are by far lefs liable to break by any alteration of weather, or in working the machine, which often was the cafe with mine before I lined them. 4thly, As a fmall cylinder thus prepared is equal in power to one much larger, that is not, and requires lefs friction, the apparatus in which it is mounted may be much contracted, and the whole, together with the perfon that turns the machine, may be eafilv fupported upon one or two fmall Itools with glafs feet, when experiments require it. With a lined cylinder 74 inches in diameter, and about 9 inches long, I have loaded three jars, that held four gallons each, to that degree as to burlt one of them, which made an explofion near to that of a pocket piftol. The cylinder was mounted in a brafs frame with a wheel and pinion ; the wheel was turned with eafe by a fmall brafs winch, and the rotation of the winch to that of the cylinder was as one to three, II. As railing the greateft quantity of eleCtrical fire was the objeCt of the firft improvement, the next B b 2 thing [ 188 ] thing was, to prelerve it when raifed, and ufe it with* out wafting any, fo that it might have its full effedt. I had obferved, that whenever a fingle wire was made ufe of inftead of a chain in difeharging the jars, the effedt- was much ftronger;. and upon making further experiments, I found that when the difcharg- ing parts were not all in clofe contadt, fuch as being fere wed tight together, or ground into one another, the effedt was confiderably diminifhed. In conftrudt> ing the difeharging apparatus, I. therefore connived that all the parts fhould be in clofe contadt, by icrew- ing grinding, or foldering, them together ; and thus the eledtrical fire exerts its whole force on the body upon which the experiment is made. III. Laftly, it often happened in difeharging the jars when loaded very high (as they mu ft be to kill a large animal, or to force the fire through bodies that make a great reliftance), that the perfons operating, notwithstanding, all their ikill and care, received the whole or part of the fhock. This has deterred many from repeating feveral ufeful experiments,., and has intimidated others that attempted to repeat them fo as to make them fail of their effedt. To remov-e this inconvenience intirely, the difeharging frame is con- trived, which,. at the fame time that it prevents the wafting of the elcdtrical fire, leaves no poftibility of the operator's ever receiving any fhock. This will plainly appear upon infpedting the figure annexed. Explanatio.no/Tab. XI. AB, a mahogany board \ \ feet long, which fup- ports the jars F, G, II, and the conductor KL. This T/u/ar. Tran,r. Vol.L VJT TAR. X! /> W8. \ if. Jtyrute *rt n//>- I [ i89 ] This board has three large holes cut through it, to fit the three jars: over thefe holes, on the under lide of the board, are nailed three tin plates, which com- municate to one another by a flip of tin, and upon which the bottom of the jars reft. Under the middle •/ of this board is alfo fixed by a wooden fcrew a cylin- drical piece of wood c, which moves up and down in the hollow of the clawed pillar D, and may be ftopt at any height by means of the fcrew E ; lo that the whole apparatus can be raifed to a height fuitable to any electrical machine to which it is applied. F, G, H, three glafs jars, about ten inches diameter, and fourteen inches high, lined infide and out with tin foyl to about two thirds of their height. A piece of wood is cemented at their top, through which there paffes a thick brafs wire, one end of which fits into a focket foldered to the conductor, and to the other end within the jar are fixed fmall wires, which fpread and form a communication between the infide lining of the jars and the conductor. KL, the conductor, a tin tube about five feet long and three inches in diameter, clofed and rounded off at each end. At the end next the machine is fix t a piece of brafs made of pointed wires in the fhape of a comb, which collects the electrical fire from the machine; at the other end is fixt a flight piece of mahogany, at the end of which two fmall cork balls are fufpended by fine threads, which balls by receding from each other, fhew to what degree the power ts railed; and when the jars are fully condenied will (land nearly upright as in the figure. When experiments require to draw a fpark from the conductor without a ihock, which we may call fingle [ I9° ] ftngle fparks, the jars are then removed, and the conductor isfupported by two glafs piiiars, fuch as are ufed in the difcharging apparatus; one end of which fits into holes made in the board at M and N, and the other end having a wire fixt to it, iupports the conductor. OPQR, the difcharging frame placed on a table, and confiding of the following pieces. QSR,a mahogany board twenty inches long and feven broad : about the middle of this board a narrow brafs plate is let into the thicknefs of the wood, reach- ing from S to a. At the extremity which projects out of the board, there is a loop into which the end of the bent wire Z is fitted by being ground into it, the other extremity receives the end of the nut S. S, a brafs nut made with a double ferew, the lower end being a male' ferew, to fafien it to the brafs plate; and the upper end a female ferew, to receive the ends oi different wires and other pieces which fit into it for performing various experiments. OQ, PR, two glafs pillars about twelve inches long and an inch thick, made with fhoulders at the end, which fit into the board QR, and the rail OP. OP, a mahogany rail three inches broad and iL thick, nearly the fame length with the board QR, which receives the upper ends of the glafs pillars. TV, a thick brafs wire, which paffes through the middle of the rail, and, by means of a ferew at d , may be ffiopt at any height. At the upper end V. of this wire is a loop, and at the lower end T a ferew, to which pieces are fixt to anfwer thofe in the nut S. W, a folid piece of brafs, through which the upright wire TV paffes, which may be fhifted to any part .[i9i] part of this wire fuitable to the height of the con- ductor, and fixt there by a fcrew. A crofs wire WX is fixt to this piece with a moveable joint towards W, fo that it may be drawn up or let down by the filk firing Y ; one end of which is fixt to the crofs wire, and the other end pafies through the loop V. X, a fmall brafs knob at the end of the wire. Z, a bent wire, which forms the communication between the difcharging frame and the outfide coating of the jars ; one end of this wire is ground into a brafs loop at a, and the other into a loop of the fame kind at et which is foldered to the tin plate that lies under the jars. i>C, an electrometer, which may be fixt on occafi- onally. When the difcharging frame is ufed, the' body upon which the experiment is made is placed between the nut S, and the end T of the upright wire, which is brought into contaCt with it ; then the wire WX is drawn up to an ereCt pofition; and, after the jars are fufficiently loaded, it is let down upon the conductor by the filk firing Y, and difcharging the jars, the eleCtrical (park in forming the circle pafies through the body. Care rnuft be taken to keep -the glafs pillars dry and clean, that none of the fire be wafied. When an animal is to be killed, he muft be fattened to a board, and his head placed between the two points S, and T. If the difcharging frame be removed, the apparatus may be ufed in medical cafes as ufualj either with- an electrometer or without. 3 XX. Two [ 192 ] XX. Two Letters from the Hon. William Hamilton, His Majefty s Envoy Extra- ordinary at Naples, to the Earl of Morton, Prefident of the Royal Society, contaming an Account of the la ft Eruption of Mount Vefuvius. Naples, June io, 1766. My Lord, \ S I have attended particularly to the I?67’ / \ various changes of Mount Vefuvius, from the 17th of November 1764, the day of my arrival at this capital, I flatter myfelf, that my obfer- vations will not be unacceptable to your lordfhip, efpecially as this Volcano has lately made a very con- liderable eruption. I (hall confine myfelf merely to the many extraordinary appearances that have come under my own infpedion, and leave their explanation to the more learned in natural philofophy. During the firft twelvemonth of my being here, I did not perceive any remarkable alteration in the mountain ; but I obferved the fmoke from the mouth of the Volcano was much more confiderable in bad weather than when it was fair j and I often heard (even at Naples, fix miles from Vefuvius) in bad weather, the report of the inward explofions of the mountain. When I have been at the top of Mount Vefuvius in fair weather, I have fometimes found fo little C *93 ] little fmoke that I have been able to fee far down the mouth of the volcano, the fides of which were incrufted with falts and minerals of various colors, white, green, deep and pale yellow. The fmoke that iflued from the mouth of the volcano in bad weather was white, very moift, and not near fo offenlive as the fulphureous fleams from various cracks on the fidesof the mountain. Towards the month of feptember laft, I perceived the fmoke to be more confiderable, and to continue even in fair weather ; and in odfober I perceived fometimes a puff of black fmoke fhoot up a confider- able height in the midft of the white, which fymptom of an approaching eruption grew more frequent daily ; and foon after, thefe puffs of fmoke appeared in the night tinged like clouds with the fetting fun. About the beginning of November, I went up the * mountain ; it was then covered with fnow, and I perceived a little hillock of fulphur had been thrown up fince my laft vifit there, within about forty yards of the mouth of the volcano ; it was near fix feet high, and a light blue flame iffued conftantly /rom its top. As I was examining this phenomenon, I heard a violent report, and faw a column of black fmoke followed by a reddifh flame, fhoot up with violence from the mouth of the volcano, and prefently fell a fhower of ftones, one of which falling near me, made me retire with fome precipitation, and alfo rendered me more cautious of approaching too near, in my fubfequent journeys to Vefuvius. From november to the 28th of march, the date of the beginning of this erruption, the fmoke encreafed and was mixed with allies, which fell, and did great Vol- LVII. C c damage [ *9+ ] damage to the vineyards in the neighbourhood of the mountain. A few days before the eruption I faw (what Pliny the younger mentions having feen, before that eruption of Vefuvius which proved fatal to his uncle) the black frnoke take the form of a pine- tree. The frnoke that appeared black in the day-time for near two months, before the eruption had the ap- pearance of flame in the night. On good friday, the 28th of march, at 7 o’clock at night, the lava began to boil over the mouth of the volcano, at firft in one ftream ; and foon after, divid- ing itfelf into two, it took its courfe towards Portici. It was preceded by a violent exploflon, which caufed a partial earthquake in the neighbourhood of the mountain, and a fhower of red hot ftones and cindeis were thrown up to a confiderable height. Imme- diately upon light of the lava, I left Naples with a party of my countrymen, whom I found as impatient as myfelf to fatisfy their curioflty in examining fo curious an operation of nature. I pafled the whole night upon the mountain ; and obferved that, though the red hot ftones were thrown up in much greater number and to a more confiderable height than before the appearance of the lava, yet the report was much lefs confiderable than fome days before the eruption. The lava ran near a mile in an hour’s time, when the two branches joined in a hollow on the fide of the mountain, without proceeding farther. I ap- proached the mouth of the volcano, as neai as I could with prudence j the lava had the appearance of a river of red hot and liquid metal, fuch as we fee in the glafs houfes, on which were large floating cinders half lighted, and rolling one over another with [ r95 ] with great precipitation down the fide of the moun- tain, forming a moft beautiful and uncommon cafcade ; the color of the fire was much paler and more bright the firfl night than the fubfequent nights, when it became of a deep red, probably owing to its having been more impregnated with fulphur at firfl: than afterwards. In the day-time, unlefs you are quite clofe, the lava has no appearance of fire j but a thick white fmoke marks its courfe. The 29th the mountain was very quiet, and the lava did not continue. The 30th it began to flow again in the fame direction* whilft the mouth of the volcano threw up every minute a girandole of red hot ftones, to an immenfe height. The 31(1 I pafled the night upon the mountain ; the lava was not fo confiderable as the firfl: night, but the red hot ftones were perfectly tranfparent, lome of which I dare fay of a ton weight, mounted at leaft 2co feet perpendi- cular, and fell in, or near, the mouth of a little moun- tain, that was now formed by the quantity of alhes and ftones, within the great mouth of the volcano, and which made the approach much fafer than it had been fome days before, when the mouth was near half a mile in circumference, and the ftones took every direction. Mr. Hervey, brother to the earl of Briftol, was very much wounded in the arm fome days before the eruption, having approached too near 3 and two Englifh gentlemen with him were alfo hurt. It is impofiible to defcribe the beautiful appearance of thefe girandoles of red hot ftones, far furpafiing the moft aftonifhing artificial firework. From the 31ft of march to the 9th of april, the laya continued on the lame fide of the mountain in C c 2 two, [ 1 96 3 two, three, and fometimes four branches, without defcending much lower than thefirft night. I remark- ed a kind of intermiflion in the fever of the mountain, which feemed to return with violence every other night. On the 10th of april at night the lava dif- appeared on the fide of the mountain towards Naples, and broke out with much more violence on the fide next the Torre dell' Annunciata. I pa(Ted the whole day and the night of the 1 2th upon the mountain, and followed the courfe of the lava to its very fource ; it burft out of the fide of the mountain, within about half a mile of the mouth of the volcano, like a torrent, attended with violent explolions, which threw up inflamed matter to a confiderable height, the adjacent ground quivering like the timbers of a water-mill; the heat of the lava was fo great as not to fuffer me to approach nearer than within ten feet of the flream, and of fuch a confiftency (though it appeared liquid as water) as al- moft to refift the impreflion of a long flick, with which I made the experiment; and large ftones thrown on it with all my force did not fink, but, making a flight impreflion, floated on the furface, and were carried out of fight in a fhort time; for, notwithftanding the con- fiftency of the lava, it ran with amazing velocity ; I am lure, the firft mile with a rapidity equal to that of the river Severn, at the paflage near Briftcl. The flream at its fource was about ten feet wide, but foon ex- tended itfelf, and divided into three branches, fo that thefe rivers of fire communicating their heat to the cinders of former lavas, between one branch and the other, had the appearance at night of a continued flieet of fire, four miles in length, and in fome parts near two [ J97 ] two in breadth. Your lordfhip may imagine the glorious appearance of this uncommon fcene, fuch -as pafles all defcription. The lava, after having run pure for about i oo yards, began to colled cinders, ftones, &c. and a fcuin was formed on its furface, which in the day-time had the appearance of the river Thames, as I have feen it after a hard froft and great fall of fnow, when begin- ning to thaw, carrying down vaft maffes of fnow and ice. In two places the liquid lava totally dif- appeared,and ran in a fubterraneous paffage for fome. paces, then came out again pure, having left thefcum behind. In this manner it advanced to the cultivated; parts, of the mountain; and I faw it the fame night, of the 12th, unmercifully de&roy a poor man’s vineyard and furround his cottage, notwithstanding the oppofition of many images of St. Januarius, that were placed upon the cottage, and tied to almoft every vine. The lava, at the fartheft extremity from its fource., did not appear liquid, but like a heap of red hot coals forming a wall, in fome places ten or twelve, feet high, which rolling from the top foon formed, another wall, and fo on, advancing flowly not more than about thirty feet in an hour. The mouth of the volcano has not thrown up any large ftones f nee the lecond eruption of lava, on the ioth of april, but has thrown up quantities of final! afhes and pumice ftones, that have greatly damaged the neighbouring vineyards. I have been fevcral times at the mountain fince the 12th; but as the eruption was in its greateft vigour at that time, I have ventured to dwell on, and 1 fear tire your lordfhip with, the obfervations of that day. 6 In [ I9S ] In my lad vifit to Mount Vefuvius the 3d 01 June* I dill found that the lava continued, but the rivers were become rivulets and had loft much ol their rapidity. The quantity of matter thrown out by this eruption, is greater than that of the laft: in the year 1760, but the damage to the cultivated lands is not to conftderable, owing to its having lpread itfelfmuch moie, and its iource being at lead three miles higher up. This eruption feems now to have exhaufted itlelf ; and I expedt in a few days to fee Vefuvius reftored to its former tranquillity. Mount Etna in Sicily broke out the 27th of april, and made a lava in two branches, at leaft ftx miles in length, and a mile in breadth, and, according to the defcription given me by Mr. Wilbraham, who was there, after having feen with me part of the eruption of mount Vefuvius, refembles it in every refpedt, except that mount Etna, at the place from whence the lava flowed (which was twelve miles from the mouth of the vulcano), threw up a fountain of liquid inflamed matter to a conftderable height ; which, I am told, mount Vefuvius has done in former eruptions. I beg pardon for having taken up fo much of your time, and yet I flatter mfelf, that my defcription, which I aflure your lordfhip is not exaggerated, will have afforded you fome amufement. I have the honour to be. My Lord, Your Lord {hip’s moft obedient and moft humble fcrvant, William Hamilton. SINCE C 199 ] Naples, February 3, 1767. Read April 2, QINCE the account of the eruption 1 767* 3 0f mount Vefuvius, which I had the honour of giving to your lordfhip, in my letter of the 10th of june laft, I have only to add, that the lava continued till about the end of november, without doing any great damage j having taken its courfe over antient lavas. Since the ceffation of this eruption, I have examined the crater, and the crack on the fide of the mountain towards Torre dell' Anonciata 5 about a hundred yards from the crater from whence this lava iffued : and I. found therein fome very curious falts, and fulphurs ; a fpecimen of each fort I have put into bottles myfelf, even upon the mountain, that they might not lcfe any of their force, and have fent them in a box dire&ed to your lordfhip, as you will fee by the inclofed bill of lading. J am fure you will have a pleafure in feeing them, analyzed. I have alfo packed in the fame box fome lava, and cinders, of this eruption ; there is one piece in particular very curious, having the exaCt appearance of a cable petrified. I fhall be very happy if thefe trifles fhould afford your lordfhip a. moment’s amufement. It is very extraordinary, that I cannot find, that any chemift here has ever been at the trouble of , analyzing the productions of Vefuvius. The deep yellow, or orange-color falts, of which there are two bottles, I fetched out of the very crater of the mountain, in a crevice that was indeed very hot,. It feems. to. me to be powerful, as it turns filver - black r 200 ] Hack in an inftant, but lias no effecft upon gold. It your lordmip pleafes, I will fend you by another opportunity fpecimens of the fulphurs and falts of the So/fa terra , which leetn to be very different from thefe. Within thefe three days, the fire has appeared again on the top of Vefuvius, and earthquakes have been felt in the neighbourhood of the mountain. I was there on faturday with my nephew lord Oreville; we heard mod dreadful inward grumblings, rattling of ftor.es, and hilling ; and were obliged to leave the crater very foon, on account of the emiffion of ftones. The black fmoke arofe as before the laft eruption ; and 1 law every fymptom of a new eruption, of which I /hall not fail to give your lord/hip an exaft account. XXL [ 201 ] Received January 30, 1767. XXI. "Ext raff of a Letter from John Howard, Efq\ ; F. R. X. to William Watfon, M. D. F. Rm R. giving fome Obfervations on the Heat of the TV aters at Bath. 62 1 7 67” ”\X7" ^ ^ ^ ^ had pleafure of fee- V V *ng you in London, you thought fome explanation of the paper, upon the heat of the Bath-waters, neceflary. The obfervations, I allure you, were made with great care. The three drd of them were made at the pump, where the waters are ufually drunk. I went feveral times into the king’s, and queen’s, baths ; and took them, where the fprings life in the king s bath, which is the warmed; part, and the mod: didant from thence the cooled. The pump in that bath correiponded with the upper pump. This I mention ; as in the other two baths, the thermometers did not nfe, by one degree, fo high as in the upper pumps 5 though I had’the pumps worked a confiderable time, to warm the pipes. The temperature of the other baths you fee in my paper. The hot bath, not being fo warm as the king’s, at fird, furprized me, until I conddered their times of filling.} and then the comparative downels of the fprings of the hot bath, to thofe of the king’s, accounted for this difference. The other obfervations are of various fprings, in and about Bath j that near St. James’s church is the Vol. LVII. D d ■ * colded. [ 202 ] oolded. The fprings, at the old and new well houfea at Briftol, are very different j but, on repeated trials, I found them fo. Obfervations oh the Heat of the Bath W iters. King’s bath pump Hot bath pump Crofs bath pump King’s bath * 1 13° 114 108 Queen’s bath * The pump in the bath Crofs bath Crofs bath pump Hot bath 99 97 100 cooled part 1 01 99 103 hotted part 97 95 9^ co°left Part 1 98 9 6 99 warmed 2I3 89 cooled part 90 warmed part 107 96 cooled part 97 warmed part The pump in the hot bath 1 1 3 Pump in the Market-place, Bath Springs on Claverton, and at late IVIr. Allen s Springs on Lanfdown St. James’s fpring water Old well houfe, Bridol New well, ditto The temperature of the above fprings taken in November, and December lad 1765, by Farcnheits fcale (Bird’s Thermometer). * Taken at three different days. John Howard, Bath, 54 47 45 43 by 76 5 [ 2 03 J XXII. Ohfervations on the Heat of the Bath and Briftol Water , by Mr . John Canton, the ftream from the common pump of the king’s bath, was raifed to 1 1 2°. The ftream from the com- mon pump of the hot bath raifed it to H4e4. At the pump of the crofs bath, it flood at no°. At noon, the heat of the (haded air was 66°, and of common water expofed to it 6i°. I found the bath water, and common water, brought to the fame degree of heat, to cool equally faft. The next day, Sept. 14, 1 was at the hot-well near Briftol, the water of which raifed the thermometer to 76°. In common water expofed to the (haded air it flood at 62°. A. M. f. r. s. Bath, Sept. 2, O. S. or the 13th N. S. 1752. Read July 3, 1767. ' FT E R pumping about 4 of an hour, a Fahrenheit’s thermometer, held in J. Canton* D d 2 XXII. A [ 204 ] Received April 3, 1767, XXIII. A Letter to Dr. William Watfon, F. R. S. from the Hon. Daines Barrington, F. R. S. on fame particular Fijh fou?td in Wales. Dear Sir, Read April 9, NO WING your attention to every thing which relates to any branch of natural hiftory, I fhall not make apologies for fending you an account of the following particulars with regard to perch in a pool of Merionethfhire ; and trout, which are found in a river of Cardiganfhire. The pool is fituated in the parifh of Trawfvynnyd, and is called Llyn Raithlyn ; as it does not lie near any road, a common traveller cannot hear any thing about it, but by very extraordinary acccident. Having been informed by JVTr. Garnons of Riwgoch, who lives near this pool, that perch were frequently caught there, which were crooked near the tail, I have, through him, procured fifh of this fort at three different times ; as I intended to preferve them in fpirits, I have always delired that they fliould be of a fmall lize. Thefe fifh were all of them moff apparently crooked in that part; which appears Rill Rronger (as I am informed) in thofe of a larger lize, and fome of them have been taken of nearly two pounds. 2 I have [ 205 ] I have never examined the back bone of ’ thefe perch, but I have now by me that of one of the trout (which I mean likewife to give you an account of) : this bone, any one may immediately fee, differs mod apparently from that of a common trout, or any other fifh,by its being crooked near the tail. I have therefore no doubt but that the back bone of thefe perch will turn out to be equally crooked. Thefe fifli are not only crooked near the tail, and for about one third of the whole length of their body there is likewife a very remarkable protuberance on each fide, which I have opened with a knife, but did notobferve it to differ materially from other parts of the flefh. I have likewife eat thefe perch, and fhould not, by the tafle, have diftinguifhed them from the common ones of the fame kind. I happened likewife (after thefe inquiries with regard to the perch of Llyn Raithlyn) to hear of trout, which were crooked in the fame part, laid to be peculiar to the river Eynion in Cardiganshire,, which is a lfnall brook, that empties itfelf into the Dovey, near Egglwys Vach, and is on the road from Machentleth in Montgomeryfhire, to Talypont in. Cardiganfhire *. * In Dalekarlia, a province of Sweden, near Fahlun, are two - fmall lakes, famous for the Angular lhape of the perch, where- with they abound, Thefe perch grow to the common Aze, and are of a good tafte, but they have all a hump on their back. This peculiarity is taken notice of in Linnaei Fauna Suecica,f p. 1 18. The country people in the neighbourhood imagine that it may be occafioned by the quality of the water in thole lakes, which •f In ftagnis Fahlnnrs huj as pifeis (Percje) varictas eft, qux fpina recurva, & corpore. omnino gibbo, fretjuens repentur. . I. have; [ 206 ] I have procured at two feveral times fpecimens of thefe trout like wife, nnd have one now by me in ipirits. They are crooked in the fame manner near the tail ; but, as the make of a trout is more taper than that of a perch, the curve does not appear. fo ilrongly : no one, however, who looks at them with any degree of attention, can have the lead: doubt oi their differing mod materially, from other fifh of the fame kind. Thefe trout are caught, only in a fmall bafon of perhaps eight or nine feet deep, which the river Eynion forms after a fall from the rocks, I have been informed, that, in a calm day, you may often fee them in this bafon j it hath fo happened that a good deal of wind hath ruffled the furface, when I have examined it. I have only to add to thefe particulars, that, by very accurate accounts from thofe, who have caught both the perch and trout, it is not above half of thefe fiffl which are thus crooked ; and that the others do not in any refpedt differ from the common ones of thefe two forts. As I have often obferved that the exidence offuch fifh was doubted by the Welfh themfelves, till I had procured thefe fpecimens, it hath occafioned my might probably be impregnated with fome mineral fait, efpecially as they are fituated near the largcft copper mine in Europe. Dan. Solander. / i - * • i There is no copper mine near Llyn Raithlyn,or the river Evnion. J Daines Barrington. inquiring [ 207 ] inquiring with regard to monocular fifh, -which are faid by Giraldus Cambrenfis, to be found in the lakes of Snowden, and from whom I fhall tranfcribe the whole paffage : <{ In fummis autem montium idorum verticibus, « duo lacus reperiuntur, fua non indigni admirati- «< one : alter enim infulam habet erraticam, ad oppo- fitas plerumque partes errabundam ; alter vero miro “ & inaudito miraculo pollet, quia cum trium gene- “ rum pifcibus abundet, anguiliis, truths, & perchiis, « omnes in eo pilces monoculi reperiuntur, oculum “ dextrum habentes, & finifho carentes : h rei tarn « novae, tamque ftupendae rationem fcrupulofus ledlor « efflagitet, affignare non praefumo.” Giraldus Cambrenfis, lib. ii. cap. io.. This writer was Archdeacon of Brecknock, and attended Baldwin Archbifhop of Canter- bury, in a progrefs which he made in the year 1188 through South and North Wales, to recom- mend a coliedtion for a crufade which was then in. agitation. We have no account of any part of England nearly fo ancient, Leland’s Itinerary having been undertaken only in the reign of Henry the Vlllth : it is not however merely the antiquity of the work, which fhould recommend Giraldus’s obfervations to the perufal of every Englifh reader ; they are at the fame time very entertaining, nor is the latinity contempt- able.. Giraldus hath in common with other ancient travellers been confidered as taking the liberties, with which they have been fo frequently charged. For my own. [ 208 ] ■own part the laft undoubted difcovery of the Patago- nian giants, mentioned, but' not credited in any previous account, will teach me not to dilhelieve entire- ly what is not a contradiction, on the very hate of it. I therefore do not abfolutely dilhelieve Mr. Grofe’s late defcriptiop of pigmies which are found in a foreft of the Carnatic, though I admit fuch fads require the ftrongeft teftimony before one fliould give a complete affent. In fhort^ I am neither for implicit belief or difbelief of fuch extraordinary fads; and it is remark- able that Ariftole, in his account of a nation of pig- mies, lays, “ this is not a fable, but a truth/’ Efi cfg o jo7to; cvrog, vrepi ov ol n vfpcuoi kcitoixovotiv' ou yoi() Tovro y.\j(l0Q, aXKct 6r R. Cook, a good mathematician, I7J/- JVa and very expert in his buftnefs, having been appointed by the Lords Commifiioners of the Admiralty, to furvey the fea coafts of New-found-land, Labradore, &c. took with him a very good apparatus of inftruments, and among them, a brafs telefcopic quadrant made by Mr. John Bird. Being, Auguft 5, 1766, at one of the Burgeo Iflands near Cape Ray, latitude 470 36' 19", the fouth-weft extremity of New-found-land, and having carefully re&ihed his quadrant, he waited for the eclipfe of the fun ; juft a minute after the beginning of which, he obferved the zenith diftance of the funs upper limb 31° 57' 00"; and, allowing for refraction and his femidiameter, the true zenith diftance of the fun’s centre 320 13' 30", from whence he concluded the eclipfe to have begun at oh 4' 48" apparent time, and by a like procefs to have ended at 311 45' zb" apparent time. N. B. There [ 2*6 ] N. B. There were three feveral obfervers, with good telefcopes, who all agreed as to the moments of beginning and ending. Air. Cook having communicated his obfervation to me, I (hewed it to Mr. George Witcheli, who told me he had a very exadl obfervation of the fame eclipfe, taken at Oxford by the Rev. Mr. Hornfby ; and he would compute, from the comparifon, the difference of longitude of the places of obfervation, making due allowance for the effedt of parallax, and the earth’s prolate fpheroidal figure } and he has lince given me the following refult: 5h 23' 59" beginn. at Oxford. ?h 7' 5" end at Oxford, o 46 48 beginn. at Borgeo Ifles. 3 39 14 end at Borgeo Ifles. 4 37 11 3 27 51 — 51 59 effeft of parallax, &c. -f 17 35 effedt of parallax, &c. 3 45 22 diff. of meridians. 3 45 i6 difS. of meridians. J. Bevis. XXV. Letter [ 2I7 J XXV. Letter to Mr, Dacofta, Librarian , &?c. to the Royal Society, from Mr. Wil- liam Martin ; containing an ExtraEl of a Letter from his Son at Bengal, on the Heat of the Climate . S I R, Head April 3©, E candid reception I met with* ,?67' JL when I took the liberty of ad- drefling you in November 1764 by my friend John ■Ellis, Efqj a cafe fomewhat uncommon, em- boldens me, at this time, to communicate^ part of a letter I have lately received from my fon, Fleming Martin, Efqj chief engineer at Bengali, dated iff odtober 1765 j giving an account of the incredible heat attending that climate, with fome other obfer- vations, &c. If you think it worthy of being com- municated to the Royal Society, it will afford me the greatefl pleafure j but this I muft beg leave to l'ubmit to your judgment, and am, with great refped. Sir, your moil obliged humble fertfant, Shadwell, 30 April, 1766. V o*l, LVII. Ff William Martin. Copy C°py of part of a Letter , from Fleming Martin, E fay chief Engineer at Bengal], dated if October, 1765, T N regard to the intenfe and uncommon heat in this **■ climate j it has been for fome time pad almoft infufterable. The thermometer was feldom under 98, and' the quickfiiver rofe at certain times of the day to 104. degrees, by the bed adjufted inftrument ; nay, I have Peen allured by fome gentlemen, that, in the camp 500 miles diftant, the thermometer often ftcod at 1 20 ; but Inch a dirrerence, I imagine, was occafcned by the badnels of the inftrument. However it is certain, that nothing could exceed the intenfe heat wc felt day and night, during the month of june. May and july were little inferior ut times, but afforded fome intermiftion ; otherwiie a very great mortality muft have attended this fettlement, though we were not without inftances of fatal effects in the month of june, when fome few individuals in found health were fuddenly feized, and died in the fpace of four hours after; but, confidering the malig- nity of the climate, we have not loft many, and I believe the generality of people are not fo intemperate as fome years paft they ufed to be ; though, from what I have feen, the beft conftitutions in the moft moderate perfons are a poor match againft a fever or other diforders in this country. I have been as free from ftcknefs, as any other perfon in the fettlement ; but I cannot fay that I have enjoyed myfelf in that degree as to be an exception ; for no man here is without complaints, and life and death . [ 2I9 ] death are fo fuddenly exchanged, that medicines have not time very frequently to operate before the latter prevails. This is generally the cafe in malig- nant fevers, which are here termed packer fevers , meaning (in the natives language) ftrong fevers. The rains have let in lince the 4th of june. We call this the unhealthy feafon, on account ot the fait petre impregnated in the earth, which is exhaled by the fun, when the rain admits of intervals. Great lick— nefs is caufed thereby, efpecially when the rains fub- lide ; which generally happens about the middle of odtober. The air becomes afterwards rather more temperate, and, till april, permits of exercife, to recover the human frame that is relaxed and worn out by the preceding feafon; for in the hot periods every relief is denyed, except riling in the morning, and being on horfe back by day break, in order to enjoy an hour, or little more, before the fun is elevated: it becomes too powerfull by fix o’clock to withftand its influence ; nor can the fame be attempted that day again till the fun retires, fo that the reft of the twenty- four hours is paflfed under the moft fevere trials of heat. In fuch feafon it is impoflible to fleep under the fuf- focating heat that renders relpiration extremely difficult ; hence people get out into the virando’s and elfewhere for breath, where the dews prove cooling, but generally mortal to fuch as venture to fleep in that air. In fhort, this climate foon exhaufts a perfon s health and ftrength, though ever fo firm in confuta- tion, as is vifible in every countenance, after being here twelve months. I have been lately informed bv an officer of diftimftion, who was formerly engi- neer at this place, that he being fent out to furvey F f 2 a fait [ 220 ] a fait lake in the month of feptember, he found the fulphureous vapours fo ftagnated and grofs, that he was obliged to get up into the tailed: trees he could find, to enjoy the benefit of refpiration every now and then ; he added that he conftantly had recourfe to fmoaking tobacco, (except during the hours of Deep), to which and to fwallowing large quantities of raw brandy (though naturally averfe to flrong liquors), he attributed his fafety. However, on his return, he was feized with an inveterate fever ot the putrid kind, which he miraculoufly furvived, though others, who attended him on the furvey, and had lived many years in the climate, were carried off, at the fame time, by. the like fever. Received' [ 221 ] Received February 5th, 1767. . ... f . . 4; * XXVI. Experiments on the Peruvian Bar% by Thomas Percival, M. D. F. R. S . I ■» t * . *■ 1 - r\\ vr; Experiment I. Read March y* N ounce of Bark coarfely powdered 7, 1767. was divided into two equal parts, one of which was infufed forty- eight hours in cold fpring water ; the other was boiled over a flow fire forty minutes, until about a third part of the water was evaporated. The infufion and decodtion were each filtered through linnen rags doubled and of equal finenefs. Four grains of Sat Martis were diflolved in an ounce of fpring water, and one dram of this folution was added to equal quantities, viz. half an ounce ; of the turbid decodtion and infufion. Each affumed a deep purple colour, fcarcely perceptibly different in degree ; though I thought the infufion, after handing a while, acquired rather a more dufky purple than the decodtion. The infufion had a deeper tinge, and more of the tafte and fmell of the Bark in fubftance than the de- codtion. Its tafte indeed exadtly refembled the Bark, after it had been broke down and chewed for fome. time in the mouth. Expe- [ 222 ] Experiment II. Equal quantities of each refiduum were boiled in three ounces of lpring water over a flow fire, for the fpace of twenty minutes. The decoctions were equally turbid, exadly fimilar in tafte ; and on the admixture of the chalybeate folution in the proportion of one dram to half an ounce, they affumed precifely the fame colour, namely a dufky brown, like chocolate, but inclining fomewhat to purple. Experiment IJI. Five ounces of each refiduum were infufed, for the fpace of forty hours, in an ounce and a half of Jamaica rum, which was lufilciently pure, and unim- pregnated with any aftringent matter from the cafk. The tinCtures were exaCtly alike in tafte and colour ; and on the addition of one dram of the chaly- beate folution, they were inftantly changed from a deep red, to a dark and dirty brown j which was precifely the fame in both tinCtures. Experiment IV. To half an ounce of powdered Bark, was added an ounce of cold fpring water. The mixture was well triturated in a marble mortar, after which it was fuffered to remain at reft until the grofs powder iubiided. The clear liquor was then carefully poured of f, and frefh water to the quantity of half an ounce was added ; the trituration wras renewed, and afterwards part of the tnenftruum poured off again as before. This method was purfued for the fpace of t 223 ] of thirty. four hours, in which time fix ounces of water were combined with the Bark. The mixture was then infufed fourteen hours without heat, and Brained off. This infufion was found to have the lfnell and tafie of the Bark, in a confiderable greater degree than either the decodion or infufion without trituration of Experiment I. and it affumed a much blacker colour, on the admixture of one dram of the chalybeate folution, than either of the two former, preparations. Experiment V: It was attempted to determine the comparative Brength, or rather aftringency, of five preparations of the Bark, viz., the ex trad, decodion, cold infufion, tindure and triturated infufion. Ten grains of the extrads carefully made, and as free from empyreuma, as this officinal preparation is generally found to be; were mixed with an ounce of hot water. But fo impeded was the folution, or, to fpeak more properly, the fufpenfion of the Bark, that in a few minutes a large powder was depofited at the bottom of the glafs. This however was fhaken up, and one dram of the chalybeate folution was. added to the mixture. The fame quantity was added to half an ounce of the decodion, infufion, tindure, (Pharm. Lond.) and triturated infufion ; the lafb affumed by far the deepeft black; the extrad approached neareft to it, and the tindure appeared to be the leaf! tinged. The decodion and infufion were precifely alike in co- lour. Expe- [ 22+ ] Experiment VI. The refiduum of the triturated infufion, Experi- ment IV. was boiled over a flow fire in three ounces of water, for the fpace of twenty minutes. The decoction when cold was ftrained off, it was of a paler colour than the decodions mentioned Experi- ment II. although there was a portion of powdered Bark, fufpended in it, which, by the trituration, had been rendered fine enough to pafs through the filter. This powder, on {landing, fubfided to the bottom of the veflel, and left the decodion much more limpid than it was before. To equal quantities of this, and of the two de- codions mentioned above, one dram of the chaly- beate folution was added j the black tinge was mani- feftly weakeft in this decodion, though the difference was not fo great as might have been expeded, from the diverfity in their fenfible qualities of tafte and frnell j owing perhaps to the fine powder of the Bark, which floated in it, and retained fome degree of its original aftringency. Experiment VII. Equal quantities of the Ample and triturated in- fufion were boiled for the fpace of feven minutes over a quick fire ; both loft their tranfparency when cool j but the latter aflumed a much more turbid appearance than the former, exceeding even that of the decodion from frefh Bark, Experiment I. and, after {landing twenty-four hours, it depofited a very copious lediment. i Ex PE- C 225 ] Experiment VIII. Half an ounce of powdered Bark was infufed forty-eight hours in five ounces of fpring water, and one ounce of white wine vinegar. The mixture was placed near a warm fire, and frequently (haken up. It was then filtered through a linen rag doubled. The tafte of the vinegar was in a good meafure covered, though the fmell was not ; but the menftruum was not fo fully impregnated with the flavour of the Bark, as the infufion Experiment I. One dram of the chalybeate folution was added to this acid infufion. At firfi: no change of colour took place, but in a few hours a flight black tinge appeared. Experiment IX. Half an ounce of powdered Bark was well tri- turated, in the manner defcribed in Experiment IV. with fix ounces of warm water, after which the mix- ture was poured into a bottle, placed near a fire, and frequently (haken up. This procefs lafted forty- eight hours. The infufion, when (trained off, was found to be more perfedtly impregnated with the Bark, than the triturated infufion in cold water, Experiment IV. as appeared by comparing their co- lour, tafle and fmell, and by the deeper black which it inftantly afiumed on the admixture of one dram of the folution of Jal martis . Experiment X. v4, 'T - i i T ’ *. * ‘ : • Half an ounce of powdered Bark, and two drams of ftone quick-lime, warm from the kiln, were Vol. LVII. G g rubbed [ 226 ] rubbed together till they were thoroughly united ; then 6 ounces of fpring water were gradually poured on, the powder and the water were well incorporated by triture, and the mixture was fet by to infufe for twelve hours. Two ounces of it were then filtered through a double linnen cloth, the remainder flood thirty- fix hours longer; and was frequently (haken up, after which it was ftrained off. The fmell of the Bark was almoft entirely covered in both the infufions, which were ftrongly impregnated with the lime ; and had an extremely difagreeable flavour. The firft was of a pale colour, and poflefled but a flight degree of bitternefs ; the latter had a deeper tinge, and was equally bitter and naufeous. Neither of them ftruck a black colour with the chalybeate folution, which, as foon as it was added, occafioned a yellow fediment, that in a few hours fubfided to the bottom of the glafs. Compared with the triturated infufion Experiment IV. thefe preparations appeared to be much weaker both in colour and tafle. The refiduum did not fenfibly effervefee with oil of vitriol. Experiment XI. The deco&ions and infufions were found to be impaired in flrength, after (landing fix or feven days, though it was the winter feafon, and the weather was feverely cold ; the infufions became paler coloured, and at the fame time depofited a (limy fed i men t. The decodtion, at the end of feven days, aflumed almoft a milky hue, and ftruck but a faint black with the chalybeate folution. The Ample infufion alfo [ 227 ] had loft much of Its aftringencyj but the two tri- turated infufions were very little altered in that refped. Remarks on the preceding Experiments. PHYSICIANS in general agree, that the Pe- ruvian Bark is moft powerful in its effects, when taken in fubftance. But as the ftomach is frequently unable to bear it, and as many patients have almoft an invincible averfton to it in that form ; it is of im- portance to determine in what preparations the vir- tues of this valuable drug are leaft impaired 5 and whether it may not be adminiftered, under a form that is elegant, palatable, and at the fame time fufficiently efficacious. The decodion of the Bark, has always appeared to me an injudicious preparation, for, though the cortex is not a fubftance of much volatility, yet there is a certain aroma accompanying it, which the heat of boiling water cannot fail to diffipate ; and confequently the medicine is deprived of one of its component parts, in which probably fome of its virtues refide. The Bark likewife un- dergoes a decompofition by boiling, the refin is fepa- rated from the gum, and remains fufpended in the watery menftruuna. This renders its appearance inelegant, its tafte naufeousj and, I fhould apprehend, muft confiderably diminifti its efficacy. For as the virtues of the Bark are ftrongeft in its native ftate, they depend in all probability on its compofition as a mixtj and muft of courfe be impaired, by the difuniting of its conftituent principles. By the firft, fecond, and third, Experiments, it appears, that the G g z cortex [ 228 3 cortex yields its virtues at leaft as perfe&iy to cold, as t6 boiling water; and the iimple infufion hath certainly many advantages over the decodtion. It is a much more agreeable and elegant preparation, and the principles of the Bark remain perfectly un- altered in it, retaining the fame proportions to each other, as in the fubftance of the drug itfelf. Nature hath fo accurately combined and blended together the gummy and refinous parts of the cortex, that by their union they become foluble in menflrua, with which when feparate they refufe to unite. Thus they reciprocally promote the folution of each other, in water and ardent fpirits ; and both the tindture and infufion are found, by Experiment, to be ftrongly impregnated with thefe two conftituent principles of the Bark. The tindture is, without doubt, an elegant and palatable preparation; but it is liable to this objection, which indeed hold equally true againfl fpirituous tin&ures in general : that a fufficient dofe of the medicine cannot be taken, on account of the heating nature of its vehicle. In low nervous fevers, hyfterical dilorders, and other cafes where it is ne- ceflary to join cordials with the Bark, an infufion of it in red port may be prefcribed with advantage. Under this form the empiric Talbot ufed to adminifter the cortex, in the paroxyms of intermittents ; and fo fuccefsful was his pradtife, that Lewis the XIVth was induced to purchafe, at a large price, the fecret of his fpecific. Orange peel is an ufeful ingredient, in pre- parations of the Bark ; it gives a grateful warmth to the infufion, and adds, 1 think, confiderably to its efficacy. The following formula is agreeable to the [ 229 ] tafte, and' well adapted tp a weak and delicate ftomach. 5^ Pulv. Cort. Peruv. Jj Cort. Aurant, incif. gfs Aq. Cinnam. ten. 5,xij Aq. Cinnam. fpir. §ij M. f. . Infufio in vafe claufo, finecalore, per fefquidiem deinde coletur. ^ The ufe of trituration, in promoting the powers of folution, is evident from Experiments IV. VI. and VII. and would have been ftill more fo, if a proper apparatus had been employed. The Count de la Garaye, a French gentleman, who is diftinguifhed for his afiiduity in applying the different branches of philosophy to the improvement of medicine, has defcribed a very convenient machine j and pointed out an admirable procefs for obtaining from veoeta- bles, by triture with- water, the matters in which their virtues chiefly refide. The contrivance is ex- tremely Ample, confiding only of a veffel, to which a churning ftaff is fitted, which, by means of a wheel, and a cord, is perpetually whirled round with a rota- tory motion. By this confiant agitation, the mod accurate diffufion is produced ; and different portions of the menftrua are in quick fucceffion applied to every part of the fol vend. From the Vth Experiment, no certain conclufibns can be deduced y except that the extra# is a much weaker preparation than is commonly fuppofech It is liable to all the objections, which have been advanced: againfl: the decoction j with this additional one, that [ 23° ] it is hardly pofliblc to make it, according to the pro- cefs of the London difpenfatory, without giving it fome degree of empyreuma. The extradl employed in my experiment was prepared by a very diligent and caretul apothecary -} yet a confiderable portion of it prefently fubfided in a powdery form to the bottom of the glafs, which on examination appeared to be the burnt parts of the Bark. How little then is this officinal pieparation to be depended upon, when we confider the careleffinefs and inaccuracy of the gene- rality of apothecaries ! It is the practice of the mod: eminent phyficians, to join acids with the Bark, in the cure of putrid difeafes ; and Sir John Pringle has oblerved, that in bilious fevers the cortex anfwered bed in rhenifti wine, after danding a night in infufion a. This fuggeded to me the Vlllth Experiment and I flattered myfelf, that by macerating the Bark in a mixture of vinegar and water, thefe two antifeptic medicines would be more accurately combined together ; and that perhaps the acid might promote the diflolving power of the aqueous mendruum. In the latter expectation it appears that I was difappointed ; and whether the former was better grounded, mud be left to abler judges to determine. The refult of this Experiment was fo contrary to my expectations, that I determined to make further trials of the effeCts of vinegar in dedroying that property, in certain vegetable fub- itances, by which they flrike a black colour with cha- lybeates, which has been long regarded as an almod indubitable ted of adringency. * Difeafes of the Army, Edit. iv. p. 213. An [ 231 ] An ounce of the infufion of chamomile flowers, was divided into two equal parts ; to one was added a dram of white wine vinegar, to the other an equal quantity of fpring water. Thus, with refpedt to dilution, they were precifely in the lame circum- fiances; a tea fpoonful of the fal martis, was then; mixed with each of them, the portion which con- tained the vinegar, fufFered no change of colour ; the other inftantly affirmed a dufky hue. The fame Ex- periment was repeated, with a very ffrong triturated infufion of the Bark; and the refult was ffill more fingular and curious. As foon as a dram of vinegar was added to half an ounce of the infufion, it changed the colour of it, from a deep and reddifh brown, to a bright yellow ; whilff the fame quantity of water had no lenfible effea: on the other portion with which it was mixed. The chalybeate folution, as in the former Experiment, was then added. It produced no alteration in the portion with vinegar, but the other was changed into a perfe&ink. That moderate heat promotes and aflifts the a&ion or water, as a menflruum on the Bark, is evident from the IXth Experiment; and it would be of advantage to determine, what degree of heat this drug will admit of, without fuftering a decompofition. It fhould however be remarked, that this infufion though fironger, had neither fo agreeable a flavour, nor was fo fenfibly impregnated with the aroma of the Bark, as the two made with cold water. In an effay on the diffolvent power of quick-lime, a very ingenious chemift has obferved, that all refi- nous bodies become foluble in water, when the cohe- fion of their particles is deftroyed, by withdrawing the [ 232 ] the fixt air which they contain. This method of folution he endeavours to apply to many valuable purpofes in medicine, and hath deferibed feveral iifeful and curious procefles for obtaining ftrong and elegant tindures of the mod adive drugs, by means of quick-lime. The firft spart of the Xth Expe- riment, ynutatis mutandis , was borrowed from him.; and it was hoped, that an efficacious and palatable infufion might with tolerable expedition be made, by the procefs which he has laid down. But the l'uccefs of my Experiment was by no means anfwer- able to the plauiibility and ingenuity of the theory, which induced me to attempt it. The infufion, after landing twelve hours, the time preferibed by Mr. Mc’Bride, was but weakly impregnated with th« Bark ; and when the maceration had been continued forty-eight hours, it by no means equalled in ftrength the preparation deferibed Experiment IV. It appears therefore that quick-lime, whatever its effeds may be upon other medicines, neither quickens nor in- creafes the folubility of Bark in water ; and it com- municates to the infufion a tafte which is intolerably naufeous and difagrceable. That the chalybeate folu- tion ffiould produce no change in the colour of thefe preparations, is agreeable to the laws of eledive attrac- tion. For the acid of vitriol, having a ftronger affinity with abforbent earths than with metallic fubftances, forfakes the iron with which it was com- bined, and unites itfelf to the quick-lime. Hence arofe the yellow ochry fediment, taken notice of in the Experiment. As the refiduum, after filtration, did not effervefee with oil of vitriol, it is evident that quick- C 233 3 quick-lime is not endued with the power of abltia&ing from Bark the fixed air which it contains. Experiment X. furnilhes no other inference than this obvious one, that the decodion and infulion of the Bark are calculated only for immediate ufe. The cortex is a fubftance of a very fermentable nature, as appears from the Experiments of Mr. M’Bride 5 and when its adive parts are diffufed in water, and feparated from thole which are merely ligneous and inert, it is not to be wondered at, that it undergoes thofe changes, to which all vegetables, when favourably circumftanced, are liable. Warrington, .February i, 1764^ Thomas Percival. • ■ ■ r -• ■ i •' '**' f > • • • . • • • «- - 1 ■ . 'tyl? ; ' i; ■ • : , ' j I1,. Vol. LVII. H h Received L 234 ] Received April 24, 1767. XXVII. An Inquiry into the probable Par- allax, and Magnitude of the fixed Stars , from the Quantity of Light which they ajford us, and the particular Circumfiances of their Situation , by the Rev . John Michell, B. D . F. R.S . * &cad May 7, andrr^ HOUGH no man can at pre- JL lent doubt, that the want of a fenfible parallax in the fixed fiars, is owing to their immenfe difiance, yet it may not perhaps be dis- agreeable to lee, that this diftance is farther confirmed by other circumfiances; for let us fuppofe them to be, at a medium, equal in magnitude and natural brightnefs to the fun, to which they feem in all refpedts to be analagous. And, having laid this down as a foundation to build upon, let us inquire what would be the parallax of the fun, if he were to be removed fo far from us, as to make the quantity of the light, which we fhould then receive from him, no more than equal to that of the fixed fiars. In order to do this with accuracy, it would be proper to compare the quantity of light ; which we at prefent receive from him, with that of the fixed fiars, by fiome fuch methods, as are made ufe of by Monfieur Bouguer ' . f *35 J Bouguer in his Trait e d'Optique a; but as my prefen t purpofe does not require any fuch exadtnefs, I fhall. deduce it in a more grofs way from faCts already well known. I fhall aflume Saturn then in oppoli- tion, exclusively of his ring (and when the earth and he are at their mean diftances from the Sun) as equal or nearly equal in light to the mod luminous fixed ftar* Now the mean, difiance of Saturn from the Sun, being equal to about 2082 of the Sun’s femidiameters, the denfity of the Sun’s light, at Saturn, will confequently be lefs than at his own furface, in the proportion of the fquare of 2082 (or 4324724) to 1. If Saturn therefore was to reflect all the light, that falls upon him, he would be lefs luminous in the fame proportion; but, befides this difference in his brightnefs, his apparent diameter, in opposition, is at mod but 105th part of that of the Sun, and confequently the quantity of light, which we receive from him, mud again be diminifhed in the proportion of the fquare of 105 (or 11025) to i . If we multiply thefe two numbers together, we fhall have the whole of the light of the Sun to that of Saturn (upon the fuppofition of his reflecting all the light, that falls upon him) as the fquare of nearly 220000 (or 48,400,000,000) to 1 ; and re- moving the Sun to 220000 times his prefent difhnce, he would Hill appear at leaf! as bright as Saturn, and his whole parallax upon the diameter of the earth’s orbit would be lefs than two feconds. This mud confequently be aflumed for the parallax of the brightell of the fixed ftars, upon the fuppofition that their light does not exceed that of Saturn. . ' uT, -\tTi OX *5 .‘6 'T -v •* '• a This work was publifhed at Paris in 1760. H h 2 By [ 23& ] By a like computation we (Ball find, that the diftance, at which the Sun would afford us as much- light, as we receive from Jupiter, is not lets than 46000 times his prefent diflance, and his whole parallax, in that cafe, upon the diameter of the earth’s orbit, would not be more than nine feconds, the light of Jupiter and Saturn, as feen from the Earth^ being in the ratio of about 22 to 1, when they are both in oppofition, and fuppofing them to refled equally in proportion to the whole of the light that falls upon them. But if Jupiter and Saturn, inffead of refledingthe whole of the light, that falls upon them, fhould in fad refled only a part of it, as for example, only a fourth or fixth (and this may very poflibly be the cafe), we muff then increafe the diflanccs computed above, in the proportion of 2 or 24- to 1, to make the Sun's light no more than equal to theirs j and his parallax would be lefs, in the fame propoition, than thofe already mentioned \ Upon the fuppofition then, that the fixed flats are of the fame magnitude and brightnefs with the Sun, it is no wonder, that their parallax flaould have hitherto efcaped obfervation, fince, if this is the cafe^ it could hardly amount to two feconds, and probably * The light, which we receive from the full Moon (according to Monfieur Bouguer’s experiments in the work above-mentioned), is only a 300000th part of that which we receive horn the Sun, whereas it ought to amount to no lefs than a 45000^ part ot it, according to the principles, which we have made ufe of in com- puting the quantity of light derived from Jupiter and Saturn ; fo that the Moon, as appears from theie experiments, refleas no more than hetween a fixth and a feventh pait ol the lig * t lat a s upon her. not [ 437 3 not more than one in Sirius himfelf ; though he had been placed in the pole b of the ecliptic, and ia thole, that appear much lefs luminous, fuch for ex- ample as y draconis, which is only of the third magni- tude, it cGuld hardly be expected to be fenfible with fuch inftruments as have hitherto been ufed in fearch of it. We have aflumed the magnitude of the fixed fhrs, as well as their brigbtnefs, to be equal to thofe of the fun ; it is however probable, that there may be a very great difference amongft them in both thefe refpedts ; and how much foever we may there- fore be wide of the truth, in attempting to fix the didance of particular fhars from this reafoning, yet there is a very great probability, that their mean diftances, fettled by this method, will not be muck out, fome exceeding and fome falling (hort of it. And perhaps the confideration, that a dar muff be a thoufand times as great, cceteris paribus , to appear equally bright, if it is placed at ten times the didance,, may ferve to make it probable, that the limits of the errors, which we are likely to commit, in judging by fuch a rule, are not fo great as we might other- wife imagine them to be. With regard to the difference there may be in the* native brigntnefs of different ftars, though it is pro- bably very confiderable, yet I think we can hardly fuppofe, that it is equal to their difference in magni- tude, at lead if we except thofe, which are fubjedt to. certain changes, and which for that reafon we may fuppofe to be luminous in fome parts of their furfaces b The latitude of Sirius being only 390 33', his parallax-, will be a. little lefs than two thirds of the whole parallax. [ 238 ] only. In other inffinces we may perhaps judge in ibme degree of the native brightnefs of different liars with refpedl to one another by their colour; thofe, which afford the whited light, being probably the mod luminous a. 3 We have at prefent no means of judging of the comparative brightnefs of the Sun and of the fixed ftars, in proportion to their refpedtive fizes, excepting from the comparifon of the Sun’s bright- nefs with that of our common fires; but the Sun’s light exceeds the light of our brightefl fires in fo very great a proportion, (viz. of fome thoufands to one) that we want ibme middle terms to be able to form any analogy, which might ferve to carry us farther. We find however in genera!, that thofe fires, which produce the whiteft light, are much the brighteft, and that the Sun, which produces a whiter light than any fires we commonly make, vaftly exceeds them all in brightnefs ; it is not therefore improbable, from this general analogy, that thofe ftars, which exceed the Sun in the whitenefs of their light, may alfo exceed him in their native brightnefs; now this is the cafe with regard to many of them; and, on the contrary, there are fome that are of a redder colour. If however it fhould hereafter be found, that any of the ftais have others revolving about them (for no fatellites fhining by a borrowed light could poflibly be vifibie), we fhould then hare the means of difeotering the proportion between the light of the Sun, and the light of thofe ftars, relatively to their refpedtive quantities of matter; for in this cafe, the times of the revolutions, and the greateft apparent elongations of thofe ftars, that revolved about the others as fatellites, being known, the relation between the apparent diameters and the denfities of the central ftars would be given, whatever was their diftance from us : and the adhial quantity of matter which they contained would be known, whenever their diftance was known, being greater or lefs in the proportion of the cube of that diftance. Hence, fuppofing them to be of the fame denfity with the Sun, the proportion of the brightnefs of their furfaccs, compared with that of the Sun, would be known from the comparifon of the whole of the light which we receive from them, with that which we receive from the Sun ; but, if they fhould happen to be either of greater or lefs denfity than the Sun, the whole of their light not being C 239 ] As far then as we can guefs at the parallax of the fixed ftars from the principles above laid down, we may realonably expedt, that it fhould be exceedingly fmall even in thofe of the firft magnitude; yet, befides the probability, that fome of them may be either lefs, or lefs luminous than the Sun, it is not fo fmall as to leave us altogether without hopes, that we may fome time or other be able to difcover it in fome of them ; for I think it is not impracticable to con- ftrudt inftruments, capable of diftinguifhing even to the 20th part of a fecond, provided the air will admit of that degree of exaftnefs; but fuch inftru- ments muft be upon a plan a good deal different from thofe hitherto made ufe of, as they would other- wile be not only vaftly too expenfive, but alfo much too great and unweildy to be of any ufe. But whatever room there may be to hope, that we may fome time or other be able to difcover the parallax of a few amongft the fixed ftars, yet at the lame time it feems probable, that we fhall never be able to difcover any fenfible magnitude in their apparent diameters, which in Sirius himfelf, if he is not of lefs native brightnefs than the Sun, muft be conftderably lefs, whatever be his parallax, than the affected by thefe fuppohtions, their furfaccs would indeed be more or lefs luminous, accordingly as they were, upon this account, lefs or greater ; but the quantity of light, correfponding to the fame quantity of matter, would {till remain the fame. T he apparent distances, at which fateliites would revolve about any ftars, would be equal to the femiannual parallaxes of thofe ftars, feen from plane. s revolving about the Sun, in the fame periodical times with themlelves, fuppoiing the parallaxes to be fuch, as they would be, if the liars were of the fame fize and dcnfity with the Sun. 4 hundredth, f 2+0 ] hundreth, probably than the two hundreth part of a fecond; fo that it would fcarcely be diftinguifhable with a telefcope, upon the former fuppofition, that fhould magnify fix, or, upon the latter with one, that fhould magnify twelve thoufand times.. Nor can we well expebt to find their apparent diameters from any occultation by the moon, fince a diameter of the hundredth part of a fecond would be covered by the moon, if it entered direbtly, in lefs than the fiftieth part of a fecond of time, and there- fore a ftar can hardly enter fo obliquely, as to appear to vanifh by degraes* no ftar probably, which the moon can pafs over, fubtending an angle half fo great. A liar might however appear to vanifh by degrees in an occultation by the planet Venus, efpe- cially if the occultation was to happen only a little before or after either ftation ; but this is an event, which can occur fo very feldom, that little is to be expebted from it; and if Venus fhould be furrounded with an atmofphere, which is probably the cafe, it might very poflibly then be of no fervice at all. For the fame realons alfo it is probable, that nothing can be determined from occultations by any of the reft of the planets, which upon other accounts are ftill lefs proper for the purpofe than Venus. There feems to be little chance therefore of dis- covering with certainty the real fize of any of the fixed ftars, and we muft confequently be contented to deduce it from their parallax (if that fliould ever be found) and the quantity of light which they afford us, compared with that of the Sun. And in the mean time, till this parallax can be found, or fomething elle may rrife to furnifh us with a more general analogy, i we . [ 24I ] ■ we can only fuppofe them, at a medium, to be equal in lize to the Sun, this being the heft means, which we have at prefent of forming fome probable con- jedture concerning the extent of the vifible univerfe. That we may be the better enabled to do this, it feems to be an objedt worth the attention of Aflro- nomers, to enquire into the exadt quantity of light, which each liar affords us feparately, when compared with the Sun; that, inftead of diftributing them, as has hitherto been done, into a few ill defined claffes, they may be ranked with precifion both according to their refpedtive brightnefs, and the exadt degree of it. A catalogue of the ftars formed upon this, plan, would anfwer feveral good purpofes ; for, befides giving us a more juft and certain notion of their general diftances, it would perhaps help us, efpecially if the parallax of a few amonglf them fhould be difeovered like wife, to trace fome analogies in their fttuation, which might enable us to determine both their diftances, and other circumftances relating to them, with ftill more probability; and it would be a ftanding regifter, by which future Aftronomers might inform themfelves of many variations, of which we are now ignorant for want of an ancient regifter of that kind. From what has been faid above, I think it is very probable, that we fhall not be a great way from the truth in eftimating the whole parallax of Sirius at one fecond, fuppoftng him to be of the fame fize and native brightnefs with the Sun; this therefore I fhall aflume as a ftandard, till fome better experiments fhall inform us more exadlly of the quantity of his Vol. LVII. I i light* C 242 1 light. Now, according to the bed judgment I have been able to make from fome grofs experiments, the quantity of light which we receive from Sirius does not exceed the light which we receive from the lead fixed flars of the fixth magnitude in a greater pro- portion than that of 1000 to i, nor in a lefs propor- tion than that of 400 to 1 ; and the fmaller flars of the fecond magnitude feem to be about a mean pro- portional between the two. Hence the whole par- allax of the lead fixed dars of the fixth magnitude, fuppofing them of the fame fize and native brightnefs with the Sun, fhould be from about 'i"r to 3'", and their didance from about eight to twelve million times that of the Sun : and the parallax of the fmaller flars of the fecond magnitude, upon the fame fup- pofition, fhould be about 12"', and their didanc.e about two million times that of the Sun. I have hitherto argued about the didances of the fixed dars, upon the fuppodtion of their being of the fame fize and brightnefs with the Sun ; and, if this was really fo, thofe which appear the brighted mud be the neared to us. That this is in general the cafe, I fuppofe, will be very readily allowed; for, though it is true, that a much greater degree of real mag- nitude may compenfate for the greatnefs of didance, and there is no reafon for afiigning any one limit to them rather than another; yet, when it is as likely that the larged dars diould be in any one part of fpace as in any other, the probability in favour of this hypothefis is very great : the real motions all'o, which have been obferved amongd feveral of the brighted of the fixed dars, is another argument to the fame purpofe; and we fhall find it dill farther confirmed C 2+3 ] confirmed by very drong arguments of analogy drawn from the circumstances of the particular fituation of the Stars in the heavens. It has always been ufual with Adronomers to dif- pofe the fixed Stars into constellations: this has been done for the fake of remembering and distinguishing them, and therefore it has in general been done merely arbitrarily, and with this view only ; nature herfelf however Seems to have distinguished them into groups. What I mean is, that, from the apparent fituation of the Stars in the heavens, there is the highed pro- bability, that, either by the original a£t of the Creator, or in confequence of Some general law (Such perhaps as gravity) they are collected together in great num- bers in Some parts of fpace, whiled in others there are either few or none. The argument, I intend to make ufe of, in order to prove this, is of that kind, which infers either defign, or feme general law, from a general analogy, and the greatnefs of the odds againSt things having been in the prefen t fituation, if it was not owing to fome fuch caufe. Let us then examine what it is probable would have been the lead apparent didance of any two or more dars, any where in the whole heavens, upon the iup- pofition that they had been Scattered by mere chance, as it might happen. Now it is manifed, upon this fuppofition, that every dar being as likely to be in any one fituation as another, the probability, that any one particular dar Should happen to be within a certain didance (as for example one degree) of any other given dar, would be represented (according to the common way of computing chances) by a fraction, 1 i 2 whole [ 244 ] whofe numerator would be to it’s denominator, as a circle of one degree radius, to a circle, whole radius is the diameter of a great circle (this lad quantity being equal to the whole furface of the fphere) that — - 2 is, by the fraction . 60 — , or, reducing it to a ^875-5' decimal form, .000076 1 54 (thatis, about 1 in 1 3 1 3 1 ) and thecomplement of this to unity, viz. .999923846, or the fraction 1 3 1 will reprefent the probability that it would not be fo. But, becaufe there is the lame chance for any one liar to be within the didance of one degree from any given dar, as for every other, multiplying this fradion into itfelf as many times as lhall be equivalent to the whole number of liars, of not lets brightnefs than thole in quedion, and putting n for this number, .999923846," or the fradior* 1 3 1 3Sl will reprefent the probability, that no one of 13131 the whole number of dars n would be within one. degree from the propofed given dar ; and the com- plement of this quantity to unity will reprefent the probability, that there would be fome one dar or more, out of the whole number n , within the didance of one degree from the given dar. And farther, becaufe the fame event is equally likely to happen to any one dar as to any other, and therefore any one of the whole number of dars n might as well have been taken for the given dar as any other, we mud again repeat the lad found chance n times, and confequently I [ 24S ] confequently the number .999923846"!”, or the fra&ion 13*3°* 13I31” will reprefent the probability, that no where. in the whole heavens, any two dars, amongd thofe in quedion, would be within the didanee of one degree from each other ; and the complement of this quantity to unity will reprefent the probability of the contrary. By a like reafoning, if we would compute the pro- bability, upon the fame fuppofition, that no two dars fhould be, one within the given didance x, and the other within the given didance £ of fome one par- ticular dar, we mud, fird, find the probability, that no dar, of the whole number of dars w, would be within the didance x from the given dar, which will — z ft'- be reprefented, as before, by the fra&ion 6S75-s'-*x 6875.5' a and, fecondly, we mud find the probability, that no. dar, of the whole number of dars n , would be within the didance z from the given dar, which, for the fame reafon, will be reprefented by the fraction. 1 n 6H75-5'~ • and the complements of thefe to unity 6875 5' will reprefent the refpe&ive probabilities of the con- trary : but the probability that two events (hall both happen, is the product of the refpe&ive probabilities of thofe two events multiplied together; if therefore we. multiply the two lad mentioned complements toge- ther, we /hall have the probability, that fome two dars would be, one within the didance x, and the other;- C 246 ] •other within the diftance z from the given ftar; and the complement of this to unity, will be the proba- bility, that it would not be fo : let us now fuppofe — to reprefent this laft quantity, and, becaufe the fame d event may as well happen in refpedt to any one ftar, as any other, multiplying this quantity into itfelf n times, according to the number of the ftars, we fhall have 31] d 1 reprefenting the probability, that no where, in the whole heavens, would be found any two ftars, one within the diftance and the other within the didance 2; from the fame ftar. If now we compute, according to the principles above laid down, what the probability is, that no two ftars, in the whole heavens, fhould have been within fo fmall a diftance from each other, as the two ftars /3 Capricorni, to which 1 (hall fuppofe about 230 ftars only to be equal in brightnefs, we (hall find it to be about 80 to 1. For an example, where more than two ftars are concerned, we may take the fix brighteft of the Pleiades, and, fuppofing the whole number of thofe ftars, which are equal in fplendor to the fainteft of vhele, to be about 1500, we fhall find the odds to be near 300000 to 1, that no fix ftars, out of that number, fc-attered at random, in the whole heavens, would be within fo fmall a diftance from each other, as the Pleiades are \ a The computations of thefe probabilities are as follow. The diftance between the two ltars (3 Capricorni is fomething lefs than 3' * ; according to tne rule above laid down, therefore, if we fuppofe 230 ftars equal to thefe in brightnefs, tne proba- [ 247 ] If, befides thefe examples that are obvious to ths naked eye, we extend the fame argument to the fmaller bility, that no two ftars of that brightnefs will be found, any where in the whole heavens, within the diftance of 3' from each other, will be reprefented by the fra&ion .l8.75’5— 68 7 5- 5 1 From twice the Log. of 6875.5 f 7*6746086] then, fubtradl twice the Log. of 3,33 See. [1.0457496] and the remainder 6.628859Q will be the Log. of the number of times, that 3.33 &c.* is contained in 6875.5 1 v‘z* 4254603 times, and confequently 4254602! 230X23° 4254603! will be equivalent to the former fradfion. From the Log. of 4254602, fubtradt the Log. of 4254603, and the remainder will be — .000000102, the proportional part for an unit in the number 4254603: this multiplied into 230 times 230, or 52900, gives — *0053958, the Log. of the whoie quantity, which correfponda to the proportional part for an unit between 80 and 81 ; this quan- tity therefore is equivalent to the fraction nearly, the comple- ment of which to unity is 8i* In the Pleiades, the five ftars Taygeta, Eledfra, Merope, Alcy- one, and Atlas are refpedtively at the diftances of 11, 19I, 24 •§, 27, and 49 minutes from the liar Maia nearly. From 7.6746086, twice the Log. of 6875.5, then, as before, fubtradt 2.0827854, twice the Log. of 1 1 (the number of minutes between Taygeta and Maia) and the remainder 5.5918232 will be the Log. of the number of times, that 77* is contained in 6875.5* VIZ> 390682 times; and confequently a fradtion, whofe denominator is this number, and whofe numerator is this number lefs by an unit, multiplied into itfelf 1500 times, will reprefent the probabi- lity, that no liar out of 1500, fcattered by chance in the whole heavens, would he within the diftance of 11 minutes from the ftar Maia. From the Log. of 390681 therefore fubtradb the Log. of 390682, as in the former example, and the remainder will be — .00000111, the proportional part for an unit in the number 390682, which multiplied by 1500 will give us — .0016650 for the Log. of the probability fought. In like manner from [ 248 ] ftars, as well thofe that are colle&ed together in Glufters, fuch for example, as the Praefepe Cancri, 7.6746086 fubtrad 2.5800692, twice the Log. of 19 | (the number of minutes between Elcdra and Maia) and the remainder will be 5.0945394, the proportional part for an unit correfponding to the natural number of which will be — .00000349; and 1500 times this quantity, or — .CO5235O will be the Log. of the quan- tity, representing the probability, that no ftar out of 1 500 fcattered by chance would be within the diftance of 19 ^ minutes from Maia. If we follow the fame rule for the three remaining ftars Merope, Alcyone, and Atlas, we Shall find the fimilar Logs, cor- refponding to thefe to be — .0076650, — .OIOO395, and — .0330300 refpedively. The natural numbers correlponding to thefe five Logs, taken in the fame order, are .996173, .988018, .982506, .977148, and .926766, which feverally exprefs the refpedive probabilities, that no ftars out of 1500 Scattered by chance, would be within the fame diftances, at which the five ftars above mentioned are found to be, from Maia. The com- plements of thefe quantities to unity .003827, .011982, .017494, .022852, and .073234, which feverally exprefs the refpedive probabilities, on the contrary, that fuch ftars would be found within the diftances above fpecified from the ftar Maia, muft all be multiplied together, to determine the probability, that thefe events Should all take place at the fame time. The Sum of the Logs, of thefe numbers is — 9 + .12791 39 or — 8.8720861, which is therefore the Log. of all thefe numbers multiplied together; and fubtrading this number from o, or, what amounts to the fame thing, changing the fign, we Shall have the Log. of the number of times that this quantity is contained in unity, that is, about 74488COOO times; a fraction, therefore, whofe denominator is this number, and its numerator unity, will reprefent the pro- bability in favour of all thefe events taking place together; and a iradion, whofe denominator is the fame number, and its nume- rator the fame number lefs by an unit, will reprefent the proba- bility of the contrary. But, as this event might as well have happened to any othpr ftar as to Maia, we muft multiply this laft tradion into itfelf 1500 times, according to the fuppofed number of ftars, to find the probability, that it Should not have happened any where in the whole heavens. Now the proportional part for an unit upon this number is — .0000000005825, which multiplied the . E 249 J the nebula in the hilt of Perfeus’s fword, 6cc. as Ccj thofe ftars, which appear double, treble, &c. when feen through telefcopes, we (hall find it fltll infinitely more conclufive, both in the particular inftances, and in the general analogy, arifing from the frequency of them. We may from hence, therefore, with the highefl: probability conclude (the odds againfl: the contrary opinion being many million millions to one) that the ftars are really collected together in clufters in fqme places, where they form a kind of fvftems, whilft: in others there are either few or none of them, to whatever caufe this may be owing, whether to their mutual gravitation, or to fome other law or appointment of the Creator. And the natural con- clufion from hence is, that it is highly probable in particular, and next to a certainty in general, that liich double ftars, &c. as appear to confifi: of two or more flars placed very near together, do really confifi; of ftars placed near together, and under the influence of fome general law, whenever the pro- by 1500 gives us — .00000087377, the proportional part for an unit in fomewhat more than 496000k But it muft be obferved, that this number is fmaller than it ought to be upon two accounts ; for, in the firft place, this method of computation gives only the probability, that no five liars would be within the diftance above fpecified from a fixth, if they occupied the largeft fpace, they poffibly could do, under that limitation ; and fecondly, we have made no allowance upon account of the different magnitudes, which, if it had been attended to, would have given a fomewhat greater refult. Thefe confiderations, however would have made the reafoning a good deal more intricate; and we have no need to defcend to minutiae* q difference in the proportion of io to 1 not at all affedling tho general conclufion. Vol. LVII. K k babilitf [ 250 ] bability is very great, that there would not have been any fuch bars fo near together, if all thofe, that are not lefs bright than themfelves, had been fcattered at random through the whole heavens. After what has been faid, it will be natural to inquire, whether, if the liars are in general collected into fyflems, the Sun does not likewife make one of l'ome fybem ; and which are thofe, amongft the fixed liars, that belong to the fame fybem with him- felf. Now, fuppofing the liars of one fyllem to be, in general and at a medium, of the fame fize and brightnefs with thofe of another, the number of liars of any one apparent magnitude would bear the fame proportion to the number of Hars of any other apparent magnitude, as they would do, in cafe all the liars were fcattered uniformly, and not in fyllems, pro- vided the eye was not placed in or near to one of thofe fyllems. And, in this cafe, the brightnefs decrealing, as the fquare of the didance inverfely, and the fphere, in which they are included, increaling, as the cube of the didance directly, the number of bars of any one degree of brightnefs and upwards, diould be, as the cube of the fquare root of that brightnefs. Sup- poling then the fainted of the 2000 blighted: bars to be lefs bright than the fainted of the fird 70, in the proportion of about 30 to 1 (and I think the difference is not lefs than this) this number is fmaller, than we might have expedted, if the Sun was not one of a fydem, in the proportion of 2000 to about j 2000 or 1 to 6; but I lhall lay the lefs brcfs upon this argument, for want of a more certain determina- tion of the proportion of light, which we receive from the bars of different magnitudes. [ 25* '] If, however, upon a more accurate examination, it fhould be found, that the quantity of light above afligned is not far from the truth, or if the difference of light (hould be greater than I have fuppofed it to be (in which cafe the argument will be ftill ffronger) ; this will add a confiderable degree of weight to the other arguments drawn from analogy, in favour of the Sun’s making one of a fyftem of ffars. If we would now inquire, which are probably thofe ffars, which compofe part of the fame fyftem with the Sun ; though it will not be poffible to point them out with certainty, yet there are fome marks, by which we may, with great probability include fome and exclude others, whilft the reff remain more doubt- ful. Thofe ffars which are found in clufters and furrounded with many others at a fmall diftance from them, belong probably to other fyffems and not to ours. And thofe ffars, which are furrounded with nebula;, are probably only very great ffars, which, upon account of their luperior magnitude, are fingly vifible, whilft the others, which compofe the remain- ing parts of the fame fyftem, are fo fmall as to efcape our light. And thofe nebulae, in which we can dis- cover either none, or only a few ffars, even with the affiffance of the beft telefcopes, are probably fyffems, that are ftill more diftant than the reff. The Pleiades, as they appear to the naked eye, have been fhewn above to be probably a fyftem by themfelves ; and if we examine them ftill farther by means of telefcopes, we {hall find, that they are furrounded with fo large a number of fmaller ffars, as to increafe the odds againft the contrary opinion many millions to one. Now fuppofing the Pleiades K k 2 to [ 252 ] to be in reality a fyftem of ftars, the probability is at leaft, I fuppofe, an hundred to one, that no one amongft them, of thofe vifible to the naked eye, belongs to the fame fyftem with the Sun ; but that thefe are only fuch ftars, as are greater than the red. The exad quantity of this probability depends upon the number of ftars, vifible to the naked eye, belong- ing to this fyftem ; the proportion, that the fpace occupied by the Pleiades bears to the whole heavens ; and laftly, how far the fituation of any one of the Pleiades falls in with the general analogy of the ftars compofing this fyftem, if any fuch general analogy fhould appear. As the nebulas, and fmaller conftellations, compofed of a great number of ftars, within a fmall diftance from one another, belong probably to other fyftems ; fo thofe, which being placed at greater didances from each other compofe the larger conftellations, and fuch as have few or no fmaller ftars near them, when examined with telefcopes, belong probably to our ewn fyftem. Moft of the ftars of the firft and fecond magnitude have this criterion to didinguifh them as belonging to the fame fyftem with the Sun, befides feveral other circumftances, fuch as their greater, brightnefs ; the proper motions *, that have 1 The apparent change of fituation, that has been obferved amongft a few of the ftars, is a ftrong circumftance in favour of thofe ftars being fome of the neareft to us. This apparent change of fituation may be owing either to the real motion of the ftars themfelves, or to that of the Sun, or partly to the one, and partly to the other.. As far as it is owing to the latter (which it is by no means improbable may in fome meafurc be the cafe) it may be confidered as a kind of fecular parallax, which, if the annual parallax of a few of the ftars fhould fome time or other be d if— covered, and the quantity and direction of the Sun’s motion 6, becfl. [ 255 3 been obferved amongft fome of them 3 their being more numerous, than we might naturally, expert in proportion to the fmaller liars, if they did not compole a part of the fame fyftem with our- felves, See. Behdes the brighter liars, it is probable there are many of thofe of the fmaller magnitudes alfo, that belong to the fame fyliem with the Sun. Now, if this fhould be the cafe, many of them being only fainter upon account of their lefs real magnitude, we may liand the fame chance of finding a parallax amongft fome of thefe, as amongft the brigheft ones, provided we pitch upon fuch as happen to belong to our own fyftem : to dired us with lome probability to thefe, we have the circumftances above-mentioned of their compofmg larger conftellations, and their having few liars lying very near to them 3 and perhaps there may be ftill a little more reafon to fufped, that thofe liars form a part of the fame fyftem with our- felves, where, belides thefe circumftances, there have been obferved changes of brightnefs, Sec. amongft feveral of them in the fame neighbourhood, fuch for inftance as the changes, which have been obferved amongft feveral of the liars in the conftellations of the Swan, Caftiopeia, See. We may, I think, alfo venture to add to thefe moft of thofe liars, that are of a redder hue than the reft, as it is probable that they are a good deal bigger, in proportion to their brightnefs, than the whiter liars [fee the laft note. fliould be difeovered likevvife, might ferve to inform us of the diftances of many of them, which it would be utterly impofiible to. find out by any other means. but r 254 ] but two]. Many of them alfohave been obferved to have a proper motion of their own, which with feveral other concurrent circumfiances tends to make it highly probable, that they are fome of the neareft to us. Having thus endeavoured to eftablifh the probabi- lity, that the Sun is one of a lyftem of liars, placed by themfelves in this part of the univerfe, I fhall next inquire into fome of the confequences of this hypothecs. Now if this is the cafe, and we fuppofe the whole number of liars, which belong to this fyliem only (excluding thole which belong to others), to amount to about 1000, we fhall find it to be an even chance, that the parallax of the neareft amongfi them does not exceed the parallax of one half that number in a greater proportion than that of 9 to 1, fuppofing the Earth to be placed in or near the centre of the whole fyftem; nor in a greater proportion than that of about 1 2 to 1 , fuppofing it to be placed very near the edge of the fyfiem ; for fuppofing 1000 points to be placed within a fphere of any given magnitude, and that they are equally indifferent to every part of that fphere, if we aflume any one of thefe points as a centre, we fhall find, according to the known dodtrine of chances, that there is an equal degree of probability whether any one of the reft fhall or fhall not fall within a fphere, defcribed about the point affumed, of about feven ten thoufandths of the fize of the whole fphere ; but the radius ol Inch a fphere is about ^ or a little lefs than _L of the radius of the whole fphere, that is about x of the radius of a fphere of half the fize of the greater one j and therefore a fphere, of about nine times this ladius. [*55] will include half the greater fphere, if its centre be affumed near the centre of the greater fphere, and a fphere of twelve times this radius will include half the greater fphere, if the point be affumed almofl in the furface of it. If we afiiime the flars belonging to our own fyflem to be about 1000 ; fince they are in all refpedts fimilar to the Sun (excepting perhaps fuch amongfl them as are liable to frequent changes), and we have nothing to determine us to one magnitude rather than another, we may mofl reafonably fuppofe the magnitude of the Sun to be a medium amongft the whole number.. Upon this fuppofition, he will probably rank only with the flars of the fourth magnitude; and his light therefore, if he was removed to the medium diftance of the other flars (viz. a diftance equal to the radius of the fphere, that would include half the flars of our own fyflem) would hardly, I think, exceed a 200th part of the light of Sirius ; and confequently, if the parallax of Sirius would be about one fecond, if he was of the fame fizeand native brightnefs with the Sun, it will be an equal chance, that the parallax of one half of the flars, belonging to this fyflem, is not lefs than one fecond divided by the fquare root of 200, that is a little more than \r" ; and it will like- wife be an equal chance, that the parallax of no one amongfl them exceeds between 9 and 12 times that quantity, or a little more than two thirds of a fecond. If, inflead of 1000 flars, we fuppofe the whole number, belonging to this fyflem, to be only about 350, the Sun will then, if he is of a medium fize amongfl them, rank probably with the flars of the third t 256 ] third magnitude, and his light, at a medium diftance, upon this hypothecs, would be, I apprehend, about a 50th part of that of Sirius. And therefore, accord- ing to the reafoning above, we fhould then find it an equal chance, that the parallax of one half of thefe 350 ftars would not be lefs than about 8//r/ 4. ; and there would be the fame chance, that the parallax of no one amongft them would be more than between 50;// and about 1" . In the former fuppofition of 1000 ftars •, the apparent magnitude of the Sun, when removed to the medium diftance; &c. it feems not improbable, that the biggeft ftar in the fyftem may perhaps exceed the Sun, in the proportion of about 1000 to 1 ; and in the latter fuppofition of 350 ftars, &c. that it may perhaps exceed the Sun, in the proportion of about 120 to 1. In whatever proportion the diameter of the Sun is greater or lefs than the medium we have taken for it in the fuppofitions above, in the fame proportion will the parallaxes be increafed or diminifhed j and in the inverfe triplicate of that proportion muft their mag- nitudes be diminifhed or increafed. Let us now examine the circumftances of the Plei- ades ; and, affuming the refpe&ive diftances of the ftars, compofing that fyftem, from each other to be, at a medium, equal to thofe of our own, let us fee what will be the confequences of this fuppofition. Now, if the Pleiades do not extend farther in the dire&ion of aline drawn between the Earth and them, than in a direction at right angles to that line (which, from their compofing a fyftem, we have a right to fuppofc they do not) we can hardly allow the mean diftance [ 257 ] diftance of thofe, that are next to each other, amongft the fix ftars vifible to the naked eye, to be greater than what would fubtend an angle, if feen diredtly from the earth, of about forty or fifty minutes. And confequently the diftance between them and the earth would be about 70 times that diftance, and their apparent brightnefs, feen from thofe that are next to each other, muff be about 4900 times as great, as it appears to us ; But ?? of the Pleiades, if I judge rightly, is not fainter than Sirius in a greater proportion than that of about 100 to 1 ; this ffar therefore muff appear brighter to the neareft of thofe fix, which are vitible to the naked eye, than Sirius does to us, in the proportion of about 49 to 1. Let us now fnppofe all the ffars belonging to the Pleiades, as well thofe difcoverable with telefcopes, as thofe which are vifible to the naked eye, to be contained within a fphere, whofe apparent diameter at the earth is two degrees ; and confequently the mean, diftance of them from a fpedfator placed fomewhere amongft them, as it might happen, would fubtend an angle, when feen dire&ly from the earth, of about a degree. Since therefore we have fuppofed the diftances of the ftars of our own fyftem to be, at a medium, equal to thofe of the Pleiades, and confequently their mean diftances from the earth to fubtend at the Plei- ades an angle of one degree, we (ball have the diftance of the Pleiades about 57 times as great as the mean diftance of the ftars of our own fyftem, from the earth. Hence, if the biggeft: of the ftars of our own fyftem fhould be at this mean diftance from us, and Sirius fliould be the biggeft, v\ of the Pleiades muft exceed it in the proportion of about 200 Vo l. ,L VII. L 1 to C 258 ] to i; for removing Sirius to 57 times his prefent didance, his light would then be fainter than it is, in the proportion of 3249 to 1, that is, fainter than q of the Pleiades in the proportion of 32.49 to 1, fup- pofing v} of the Pleiades, as above, to afford us a hundredth part of the light of Sirius ; but the mag- nitude of liars, fuppofing them equally luminous and their didance to be given, is as the cube of the fquare root of their brightnefs; and therefore v\ of the Plei- ades, upon this fuppofition, mud be bigger than Sirius in the proportion of the cube of the fquare root of 32. 49 (that is 185) to 1. But I mud obferve, that according to general (and, I believe, 1 may fay univerfal) analogy in all thofe nebulae, in which we difcover dars bigger than the red, thefe dars are placed towards the middle of their refpeCtive fydems, and, if therefore the fame thing obtains with regard to our own fydem, this will make >7 of the Pleiades dill fomething greater. If the didance of the Pleiades is greater than the mean didance of the dars of our own fydem, in the proportion of 57 to 1, it would be neceffary, in order to make dars, of the fame real magnitude amongd the Pleiades, equally vidble to us with thofe of our own fydem, to take in a pencil of rays of a greater diameter, than the pupil of the eye, in the fame pro- portion : this, after proper deductions for the lofs of light, could not well be effected by an objedt lens of lefs than two feet aperture. Now Dr. Hooke tells ns, in his Micrographia, that, with a telefcope of twelve feet length, he difeovered in the Pleiades 78 [ 259 1 if a telefcope of twelve feet length, the aperture ot whofe objed lens was probably lefs than two inches, increafed the number of vifible (bars in the Pleiades to 78, we may well fuppofe, that with an objed lens of two feet diameter, they would amount to more than 1000. What this number would be muft depend however upon the gradation of real magnitude amongft the ftars of that fyftem, to which there mud; necef- farily be fome limit, and it is not therefore improbable, that obfervations of the increafe of the number of bars amongft the Pleiades, &c. with telelcopes of larger apertures, efpecially if this was carried on to very large ftzes, might ferve to infoim us or many circumftances, both with regard to this gradation, and perhaps fome other things, that would enable us to jud ge with more probability concerning the diftances, magnitudes, &c. of the ftarsof our own fyftem. If we now imagine a fpedator amongft the Pleiades - to take a view of this fyftem from thence, fuppoftng the diftance, as before, 57 times the mean diftanceof our own ftars, we fhould appear to him as a nebula, in which there would be no ftar bright enough to be diftinguifhable by the naked eye j and with a telefcope, the aperture of whofe objed lens was two inches, he would hardly, I fuppofe, be able to diftinguifh more than half a fcore ftars at the utmoft. Having hitherto fuppofed the diftances of the ftars of our own fyftem to be the fame with thofe ot the Pleiades, and examined the appearances according to that hypothefis, let us now, inftead of their diftances, fuppofe their magnitudes to be the fame. This would make this fyftem, as leen from the Pleiades, to fubtend an angle of about twelve degrees inftead of two, L 1 2 and [ 26q ] and about half a fcorc of the biggeft ftars would be there vifible to the naked eye ; but a telefcope, whofe object lens was of two inches aperture, would in that cafe, I apprehend, take in almoft all the ftars belonging to this fyftem of the fourth magnitude and upwards. Thefe appearances fall in lets, I think, with the general analogy of what we fee in the heavens, than the former fuppofition ; but for want of more obfervations I cannot fay this with any certainty : in the mean time however till we have fomething farther to go upon, it may not perhaps be amifs to take a kind of medium between the two, and fuppofe the Pleiades to be at about twenty times the mean diftance of the ftars belonging to our own fyftem, in which cafe y\ will exceed the biggeft of thefe, in the pro- portion of about eight or ten to one; or it will exceed the Sun, according to our former fuppofitions of his being of a medium fizeamongft 1000 or 3,50 ftars, in one cafe in the proportion of about eight or ten thoufand, and in the other, about a thcufand or twelve hundred to one; its parallax in the former cafe being about 36//;/ and in the latter about 1 I fhall conclude this inquiry with one obfervation more, concerning the appearance of the ftars of our own fyftem, as feen from great diftances. Whatever then the real diftance and magnitude of thefe ftars may be, provided we have not been greatly out in aligning the proportion of their light in refpeeft to that of the Sun and one another, if they were to be feen from a diftance, at which the whole fyftem would not fubtendan angle of more than lix or eight minutes, it would appear only as a nebula, no fingle ftar being vifible with perhaps any telefcope, that has ever yet been [ 261 ] been made ; for at this diftance, the didance between the earth and the biggeft ftar of this fyftem not fab- tending an angle of more than about three minutes (that is, about a twelve hundredth part of the radius) the bars of this fyftem muft appear lefs luminous than they do to ourfelves, in the proportion of the fquare of 1200 (or 1440000) to 1. And fuppofmg the light of Sirius to exceed that of the Ieaft vifible ftar in the proportion of about 1 200 to 1 , the brighteft ftar there- fore would ftill require to have its light increafed in the proportion of 1200 to 1, before it would begin to be diftinguifhable. To do this would require a tele- fcope, that fhould take in a pencil of rays of a larger diameter than the pupil of the eye, in the proportion of 35 to 1, that is, a pencil of about a foot diameter, exclufive of deductions ; for the pupil of the eye is not lefs than a third of an inch in diameter, in a clear ftar-light night, when there is no Moon ; but to obtain fuch a pencil, we muft not make ufe of a refracting telefcope (with two lenfes only) of lefs than 1 5 inches, nor a refle&or of lefs than nearly two feet aperture. This may ferve to fhew us, that thofe nebulae, in which we cannot difting.uifh any ftars, may yet reafonably be fuppofed to confift of ftars, though too far diftant to be fingly viftble ; fince this would be the cafe with our own fyftem, feen from as great a diftance as we may well fuppofe thofe nebulas to be from us, if we judge of it from the magnitude of the vifible area, which they occupy in the heavens. Of the twinkling of the fxedfars. Having never yet feen any folution of the twink.- Lng of the fixed ftars, with which I could reft Tatis- fled,. L 262 3 fied % I (hall offer the following, which may not per- haps be found an inadequate caufe of that appearance ; at leaft it has undoubtedly fome ffiare in producing it, efpeciaiiy in the fmaller ftars. It is not, I think, unreafonable to fuppofe, that a fingle particle of light is fufficient to make a fenfible impreffion upon the organs of fight. Upon this fuppofition, a very few particles of light, arriving at the eye in a fecond of time, will be fufficient to make an objedt vifible, perhaps not more than three or four; for though the impreffion may be confidered as mo- mentary, yet the perception, occafioned by it, is of a much longer duration : this fufficiently appears from the well-known experiment of a lighted body whirled round in a circle, which needs not make many revolutions in a fecond, to appear as one continued ring of fire. Hence then it is not improbable, that the number of the particles of light, which enter the eye in a fecond of time even from Sirius himfelf, may not exceed three or four thouland ; and from liars of the fecond magnitude, they may therefore probably not much exceed an hundred. Now the apparent increafc and diminution of the light, which we obferve in the twinkling of the ftars, feems to be repeated at not very unequal intervals, perhaps about four or five times in a fecond : why may we not then fuppofe, that the in- * Some aftronomers have lately adopted, as a folution of this appearance, the extreme minutenefs of the apparent diameters of the fixed ftars, which, they fuppofe, muft, in confequenee ot this, he intercepted by every little mote, that floats in the air ; but, that an object fliould be able to intercept a ftar from us, it niuft be large enough to exceed the apparent diameter of the ftar by the diameter of the pupil of the eye; fo that, if the ftar was a mathematical point, it muft ftill be equal in fize to the pupil of the eye. equalities. [ 263 ] equalities, which will naturally arife from the chance of the rays coming fometimes a little denfer and fometimes a little rarer, in fo fmall a number of them as mull fall upon the eye in the fourth or fifth part of a fecond, may be fufficient to account for this appearance ? An addition of two or three particles of light, or perhaps of a fingle one upon twenty, efpe- cially if there fhould bean equal deficiency out of the next twenty, would I fuppofe be very fenfible : this feems at lead; probable from the very great difference in the appearance of ftars, whofe light is much lefs different than, I imagine, people are in general aware of; the light of the middle-moff ftar in the tail of the great Bear does not, I think, exceed the light of the very fmall ffar next to it, in a greater proportion than that of about fixteen or twenty to one ; and Moniieur Bouger tells us, in his Traite d’Optique before-men- tioned, that he finds a difference in the light of objedts of one part in fixty-fix fufficiently diffinguiffiable. It will perhaps be objected, that the rays coming from Sirius are too numerous to admit of a fufficient inequality, arifingfrom the common effedt of chance, fo frequently as would be neceffary to produce this effedt, whatever might happen in refpedt to the fmaller ftars j but till we know what inequality is neceffary to produce this effedt, we can only guefs at it either one way or the other ; there is however another circum- ffance, that feems to concur in the twinkling of the ftars, befides their brightnefs, and this is a change of colour. Now the red and blue rays being very much fewer, I apprehend, than thofe of the intermediate colours, and therefore much more liable to inequality from the common effedl of chance, may help very much to account for this phamomeribn, a fmall excefs Vol. LVII. L 1 4 or [ z6+ ] or defedt in either of thefe making a very fenfible difference in the colour. It will now naturally be afked, why the frequency of the changes of brightnefs fhould not be often much greater, as well as fometimes lefs, than that above- mentioned, and why the interval of the fourth or fifth, or fome fuch part, fhould be pitched upon, rather than the fortieth or fiftieth part of a fecond, or than a whole fecond, &c. for, according to the length or fiiortnefs of the time affumed, the changes, that will naturally occur, from the effedt of chance, will be fmaller or greater in proportion to each other. The anfwer to this queflion will, I think, tend to render the above folution more probable, as well as to throw a good deal of 1 ght upon the whole fubjedt. The lengths of the times then between the changes of brightnefs, if I am not mif- taken, depend upon the duration of the perception before mentioned, occafioned by the imprefiion of the light upon the eye, than which they feem to be neither much longer nor fhorter. Whatever inequa- lities fall within a much fhorter time than the conti- nuance of this perception, will neceflarily be blended together, and have no effect, but as they compofe a part of the whole mafs ; but thofe inequalities, which fall in fuch a manner as that they may be affigned to intervals nearly equal to, or fomething greater than the continuance of this perception, will be fo divided by the imagination, which will naturally follow, and pick them out as they arife. END OF PART I. PHILOSOPHICAL TRANSACTIONS VOLUME LVII. PART II. | T * , : : j A ' % iijrna v ii v c. J 1 U' . • ' “Tv 7)0 >u; PHILOSOPHICAL TRANSACTIONS, GIVING GOME ACCOUNT OF THE Prefent Undertakings, Studies, and Labours, OF THE INGENIOUS, IN MANY Coniiderable Parts of the WORLD. VOL.LVII. PART II. For the Year 1767. LONDON: Printed for L. Davis and C. R e y m e r s. Printers to the Royal Society, againfl: Gray s- Inn Gate , in Holbourn, mTdcc.lxviii. 4# J A > l H c O ^ O 1 J II T R A q ■)*— -t ,11. • . • ■ • • . .ix! Ju .bad*, j arn itrc f j. iftnjrtaJifW nHo[ aVv .XIXX fttM 11VJ . PHILOSOPHICAL TRANSACTIONS. XXVIII, cTher?72ometrkal Obfervatiom at Derby, by Mr. John Whitehurft, com- municated by Charles Morton, M, D, Dear Sir, Read May i^TT 'j £ experienced a much greater de- W gree of cold at Derby, in the late froft, than perhaps was ever obferved in England ; and the quick tranfitions were no lefs remarkable. On Sunday the 1 8th of laft month, at nine of the clock in the evening, my thermometer flood at 20. At half an hour after nine, nearly one degrew below o. At feven the next morning, 30. external air. I am, Sir, PART II. Received April 9, 1767. Sec. R. S. Your moil obedient fervant, Derby, John Whitehurft. M m XXIX. An Feb. 15, 176;. Vol. LVII. [ ] XXIX. An Attempt to interpret the Legend mid Infcription of a very curious Phoenician Medal y never hitherto explained . In a Letter to the Right Honourable the Earl of Morton, Prejident of the Royal Society , from the Rev. John Swinton, B . D. F. R. S. Member of the Academy degli Apatifti at Florence, and of the Etrufcan Academy of Cortona in Tufcany. My Lord, Read May 21, A P T. Swinton fome time fince put into my hands a very curious filver coin, taken, as he informed me, out of your Lord- lhip’s valuable cabinet. He at the fame time alfo im- parted to me your Lordfhip’s commands, relative to that coin. In obedience to which, I now do myfelf the honour to fend you the following interpretation of the legend and infcription it exhibits. This, as I cannot help believing it true, or at leaft not very remote from truth, may poflibly, I would flatter myfelf, prove not altqgether unfatisfa&ory or unacceptable to your Lordfhip. I. On one fide (fee Tab. XII.) the medal prefentsto our view Jupiter fitting in a chair, with his eagle before him, a bunch of grapes in his right hand, and a fort of lance, or rather flaff, as it fliould feem, in his left. Behind him the legend nn 7}0>baal tarz, orBAAL tars, formed of Phoenician letters, may be difeerned ; 4 and I . [ 26y ] and the element B, inverted, is vitible under the chair. On the other fide we difcover a lion feizing upon, or rather tearing, a flag} over and under which the two Phoenician words n!3 mo, mizze- rag moth, or MUTH, in their proper characters, unlefs I am greatly miftaken, Teem clearly to appear. The workmanfhip of all the figures, but particu- larly of the lion and the flag, is finifhed in a high manner, and exquifitely fine. Several (i) fimilar medals have been published by Lord Pembroke, M. Morell, and M. Pellerin. Amongd thefe we find four in Lord Pembroke’s noble cabinet, emitted from the fame mint, and done in the fame tafle, with that I am here confidering, three of (2) which exhibit a lion tearing a bulk Not one of the legends, or infcriptions, with which they arc adorned, has been hitherto explained. A proper and accurate draught of the medal before me has never yet, as I apprehend, been given us, by any antiquary, or author whatfoever, and therefore the piece itfelf may pafs for an inedited coin. II. That the legend of this medal is formed of the letters Beth , Ain, Lamed , Lhau, Rejch , and Zain, from which refult the words baal tarz, or baal tars, will, I flatter myfelf, not be denied by the learned. The firfl character flrongly refembles the (1) Numifm. Antiqu. (Ac. a Thom. Pembr. et Mont. Gomer. sCom. Collect. P. 2. T. 87. Morel. Specim. Univerf Rei Mam- mar. Antiqu. (Ac. P. 24.5. Tab. xxvi. Lipfise, 1695. Peller. Re- cueil de Me dailies de Peuples et de Vi lies, (Ac. Tom. Trois. PI. CXXII. A Paris, 1763. (2) Numifm. Antiqu. a Thom. Pembr. et Mont. Gomer. Com. Colleft. ubi (up. Mm2 Beth [ z68 ] Beth of the (3) Palmyrenes, which had moft cer- tainly the fame origin with the Phoenician Beth . Nor can it be taken here for any other element. Befides, the common Phoenician form of that letter and the character in queflion are (4) promifcuoufly ufed on this fpecies of coins. The fecond element is Jin, as appears from other (5) authentic monu- ments. The third is Lamed , though not fo well preferved here as on fome other fimilar (6) coins. The fourth," at fir ft fight, will be pronounced Thau, by every one at all verfed in this branch of literature.. That the fifth is Refch, we may fairly prefume; as the fimilar letter Daleth appears (7) open at the top, like this, cn a medal of Sidon, publifhed by M. Pellerin, and as fuch a figure of Refch a&ually prefents itfelf to our view on the reverfes of two of my Tyrian (8) coins. Nor does the conefpondcnt character on another of thefe Phoenician medals, ^a draught of which has been given (9) us by M. Morell, recede much from the common Phoenician form of Refch , which on thefe pieces likewife fome- times occurs. The fixth is Zain , as has been (10) rendered elfewhere fufficiently evident. What, the inverted B, under the chair, was intended to denote, unlefswe may confider it as the initial letter < ?\ Philof Tranfaft. Vol. XLVIII. p. 693, 740, (4) Peller. ubi l'up. PI. CXXII. p. 164. (0 Philof. Tranf. Vol. Bill. p. 282. & Vol. LIV. Tab. xxiv. Peller. Recueil dc Medail de Peup.etdcl u.be. 1 oni. Trois. P- PI- CXXII. A Paris, 1763. (7) Peller. ubi fup. Tom. Sec. PI. LXXXII. N. 21. p- 226. See Tab. XII. N. 2, 3. . nVVIT (n) Morel, ubi ("up. Peller. Tom. 1 rots. PI. CXAll. (?o) Philof. Truf. Vol. XLVIII. p. 7*5* & Vol‘ ^TII‘ p. 283. [ 269 ] of the firft word b aal, it may perhaps be not fo eafy to decide. From the two Phoenician proper names baal tarz, or eaal tars, it feems highly probable, that the medal was ftruck at Tarfus, the capital of Cilicia, feated in a country abounding with wild beafts, ( 1 1) particularly lions and flags, and famous for the birth of the great apoflle St. Paul. For baal tarz, or baal tars, is equivalent to Jupiter Tar.sen.sis, Jupiter of Tarsus, or the lord of Tarsus. So we find this Pagan di- vinity denominated (12) on coins ZETC KACIOC, Jupiter Casius, ZETC KAniTXIAlETC ANTI- OXEXXN, Jupiter Capitolinus Antiochen- s 1 u M , ZETC CTPATHTOC AMACTPIANflN, Jupi- TER IMPERATOR A M AS T R I A N ORUM , &C. Alld, upon (13) a coin of the emperor Hadrian, we read. AIOC TAPCEfiN METPOnOAEaC, Jovis Tar- sensium metropoleos, or Jovis Tarsensis, of Jupiter of Tarsus, the very appellation given this pretended deity by the medal now in view. Nay, he is there exhibited with his eagle, and fitting in a chair, as he appears upon the Phoenician coin I am endea- vouring to explain. The notion here advanced is alfo ftrongly fupported by two pieces of the emperor Gordian, publifhed by Dr. Vaillant. One of thefe on the reverfe prefents to cur view Bacchus, with a (ij) /Elian, de AnimdL Lib. V. c. lvi. Boch. Chan. Lib. I. c. v. p. 376, 377. Francof. ad Mcen. 1681. (12) Joan. Vaill. Nujnifm. Imp. Align ft . id Cezfar. d Pop. Rom. Dit, Greece loquent. &c. pefT. in i ike manner the great deity of. Bcrytus went under the appellation of eaal berith, according to Bochart. Boc’n. ubi fup. p. S59. (13) Joan* Vaill. ubi lup. p. 36. Amftdaedami, 1700. "c bunck [ 27° 3 bunch of grapes (14) in his right hand, as Jupiter ap- pears on the medal before me, attended by the in- fcription TAPCOT METPOnOAEnC, &c. Tarsi metropoleos, &c. andtheother is adorned with the fame infcription, and a lion tearing a (15) bull, the very fymbol that occurs on three of Lord Pem- broke’s (16) coins, fo perfectly fimilar to that which is the objed of my attention here. In farther evidion of the point I am contending for, I muft beg leave to remark, that two pieces of Tarfus with Jupiter Tarfenfis on the reverfe, in the very fame attitude, and, in other refpeds, refem- bling the figure of the fame deity on the medal now confidered, have been lately (17) published by M. Pellerin. From the coin of Gordian (18) adorned with Bacchus on the reverfe, holding a bunch of grapes in his right hand, we may infer, not only that Bac- chus was worlhiped at Tarfus, but likewife that wine was made in the diftrid appertaining to that city. This will eafily and naturally account for the grapes held by Jupiter, or Baal, in his right hand, on the piece lam attempting toilluftratehere. It muft be farther remarked, that fuch medals as this, as well as many others, are dug up in. the. neighbourhood (19) of Kepfe, the Seleucia Pieria of theantients, which flood at no very great diftance from (74) Joan. Vaill. ubi (up. p. 157. (15) Id. Ibid. (ib; Numifm. Antiqu. (Ac. a Thom. Pembr. et Mont. Gomcr. Com. Collett, p. 2- I • 87* (17) Peller. ubi fup. Tom. Sec. Pl.LXXIV. p. 175 177* A Paris, 1763. (18) Joan. Vaill. ubi fup. p. 157. (10) Pococlce’s Defcript. of the Eq/1, Vol. II. p. 1S6. t mount [ 27 1 ] mount Amanus and the borders of Cilicia. This, in conjunction with what has been already offered in fupport of my prefent opinion, will amount to the ftrongeft preemption, if not an irrefragable proof, that the piece in queftion was ftruck at Tarfus. The late Mr. Arthur Pullinger fhewed me two fimilar coins, found near the place juft mentioned, which he purchafed at Aleppo, and brought with him to England out of the Eaft. That the Phoenician name tarz fhould have anfwered to the Greek TAPIOS, and the Latin Tarsus, can be no matter of furprize to any perfon at all verfed in oriental literature. For ’tis too well known to hand in need of a proof, that OS is a pure Greek termination, and vs a Latin one, fuperadded to the Phoenician word. And that the Greeks (20) not infrequently converted Zain into Sigma, as the Latins did into S, is a molf obvious truth. Many inftances of fuch converiions, in oriental names adopted by thofe nations, might, with the utmoft fa- cility, be produced, III. With regard to the characters on the reverfe, their powers feern fufficiently deducible from other monu- ments heretofore explained. The fir ft and fifth will undoubtedly be taken for Mem. The fecond points plainly at Zain. The third will be looked upon* either as Daletb , Caph, or Refch ; though, if the fenfe be duly attended to, I think we muff pro- (20) Boch. Chan. Lib. 1. c. xxvii p. 559. c. vi. p. 390. & alib. Francof. ad Mcen. 1681. The Arabs, after the conquc-ft . of Syria, adopted the Greek, or Latin, name; which is evi- dently not fo antient as the Phoenician Hi"!, tarz, or tars. n ounce - [ 272 ] nounce it Rejch. The fourth will be allowed to re- prefent Ghimel , as that element appears in fome of the (21) Palmyrene infcriptions, and particularly that found (22) at Teive. The fixth, as I appre- hend, muft pafs for Thau. Now the words formed of thefe letters, no JDtD, mizzerag moth, or mtsserag mvth, may be rendered ab implec- TENDO (c'OLLIGANDO, CONNECTENDO, &C,) mors, or rather a connectione (colliga- T ION E, IMPLEXV, CONGRESSV, &C.) MORS, from the connection (seizure, attack, &c.) comes death. In Hebrew the fecond letter of the fir ft word here is Sin, in Chaldee Samech , and in Arabic Ze. That in all thefe languages, however, the term is nearly the fame, and has nearly the fame fignification annexed to it, we learn (23) from fome of the beft lexicographers. Nor can any thing be more confonant to the na- ture of the fymbol on the reverfe than the fenfe here atfigned the infeription. They may both perhaps be luppofed to have alluded to the Indian mannei of hunting ftags with lions, mentioned by /Elian (24), which might formerly likewife have prevailed in Cilicia j or to the production of thofe (25) animals, which were anciently fo numerous in that country ; or laftly to fome remarkable event, that not impro- •'(21) Pbilofoph. Tranfaft. Vol.XLVIII. p.693, 74°* (22) See Vol. LV1. Tab. I. Fig. 1. p. 5. (23) Va1. Schind. Johan. Buxtorf. F. Lex. Cbald. Tarn. & Rabbin. Leonh. Reckenb. & Jo. Chrift. Clod. Lex. Hebr. Selcfl. Lipfiae, 1744* n (24) ^Elian. de Animal. Lib. XVII. c. xxvi. P- 99°* L'°" Ionix Allobrogum, 1616. (25) ./Elian. de Animal. Lib. V. c. Ivi. Boch. Chan. Lib. J. c. v. p. 376, 377. Francofurti ad Mcenum, 1681. sj DhK/J Y [ 273 ] "bably happened about the time the medal was ftruck. IV, The laid remark naturally leads me to the age of the coin I am endeavouring to explain, to which perhaps a pretty near approach may be made. 1 formerly publifhed a fimilar (26) medal, that, unlefs I am greatly deceived, firfl appeared in fome part of the Parthian territories. It prefented to our view on one fide Jupiter Tarfenfis, as he is exhibited by the piece before me, and two words perfectly agree- ing with thofe attending him on this piece, being formed of the very fame Phoenician characters. On the other- we perceived a human figure fitting in a chair, with an arrow in both its hands, before which flood a bow, a weapon not feldom occurring on the reveries •of the Parthian coins (27). Hence it fhould feem, (26) Philofoph. Trarifaft. Vol. LI. Tab. xvii. p. 683. The Parthian kings fometimes wore a fort of long breeches, reaching down to their ancles, fimilar to what is exhibited by the Coin here referred to, as we learn from the reverfeofa Parthian medal now in my pofTefTion, a draught of which may be fecn in (a) Tab. XII. N. 1. This will ferve {fill farther to evince the trurh of the point here contended for. That the coin by me formerly publifhed ought to be ranked -among thofe (truck in the Parthian territories, will be rendered hill more probable by certain human figures that occur amongffc the ruins of Perfepolis ; which are (b) adorned with a fort of cap, not a little fimilar to that on the head of the prince prefented to our view by this coin. The bow and arrow likewife on it, (c) vifible alfo on a very curious Daric, will con- firm what has been here advanced, in fupport of my prefent opinion. ( a) Philof. TranfaEi, Vol. LVII. Tab. XII. N. j. p.265. (b) Engel. Kasmpfer. Amccnitat. Exotic. &c. p. 311. Lcnigoviae, 1712. (c) Hyde Hiji. Relig. Veter, Fvrfar, &c. p. 113. Ox on, 1760, Vol. LVII. N n that [ 374 ] that thefe pieces were ftruck at Tarfus, when the Parthians (2%) were mailers of Cilicia. Now I cannot learn from hiftory, that they were ever poiTeffed of that province before the year of the Julian Period 4673, which preceded about forty one years the birth of Christ, when (29) it was reduced by Labienus ; nor after the following year, when they were overthrown, and expelled the Roman territories (30), by Ventidius. Perhaps (28) That the piece before me is of Parthian original, feems likewife farther to appear from a complex figure reprefenting a lion tearing (<7) ahull, the very type on the reverfesof feveral coins, men- tioned in the beginning of this paper, and agreeing in almoft all re- fpe£s with this piece, to be met with in the ruins of ( a ) Perfepo- Jis. For that part of thofe ruins, at leaft, are Parthian remains of antiquity, I have (b) formerly obfefved. But fhould any one confider them as Perfian monuments, and even as prior to the reign of Alexander the Great, yet flill the point I would in fome imafure fupport by them will thereby be rendered probable, if not inconteftable. For the Perfians and the Parthians may be looked upon, with fufficient propriety, as one and the fame na- tion ; the fame habits, the fame cuftoms and manners, and the fame religion, feeming antiently to have prevailed amongft them. Whenever therefore we find a lion tearing a bull, or a flag, on any Greek medals, we may conclude it not improbable, that the prince or people to whom they belonged adopted a type of Parthian, or Perfian, extraction. (c) Gefner affigns the coin I am confidering a place amongft thofe of the Syrian kings, but knows not what to make of it. He only ©bferves, that Morell takes it to be a Parthian medal, and that others entertain a different opinion ; not attempting, in any part of his book, to oblige the learned world with an explication, of it. (29) Dio, Lib. xlviii. L. Flor.Lib. I V. c. ix. Plutarch, in Anton, Appian. Alexandria in Syriac. & Parthic. & dc Bell. Civil. Lib. v. (^o) Dio, ubi (up. Appian. in Parthic. Li v.Epit. Lib. cxxvii. L. Fior. Lib. IV. c. ix. Plutarch, in Anton. (a) F.ng. Ksmpf. Amcemtat. Exotic, p. 339. Lemgovix, 171a, (b) Philof. ‘ Tranfat 1. Vol. XL1X. P. i. p. 598, 599, 6eo, (r) Gcfn, Tab. 'Reg. Syt.lX, N. 2. Tignri, 17^8. therefore t 27$ 1 therefore we may be permitted to fuppofe our medal to have been emitted from the mint at Tarfus in one of thofe years. If this fhould be admitted by the learned, and I can fee nothing unreafonable in fuch a fuppofition, we may naturally enough account both for the fymbol and the infeription. For the Par- thians at this time had the Romans in fuch contempt, by reafon of their former victories over them, that a body of their forces advancing to the relief (31) of Labienus, then incamped on Mount Taurus, at no very great diftance from them, engaged a Roman army, before their junction with that general. Be- ing therefore overthrown in this battle by Ventidius, (32) who commanded the Romans, and molt of them cut in pieces, they received the reward juftly due to their temerity and preemption. This cer- tainly gives us reafon to believe, that the fymbol and infeription I am now upon pointed at the victories gained by the Parthians over the Romans, about the time above mentioned ; and that they were intended to perpetuate the memory of thofe vidories, to the remoteft periods of time. In farther fupport of what has been here ad- vanced, it may not be improper to obferve, that a fimilar (33) medal publifhed by M. Pellerin feems to me to be undoubtedly Parthian. On one fide we difeover Hercules, with a club in his right hand, and a lion’s fkin in his left, as he appears on a coin of Tarfus (34), together with a bow, a fymbol not (31) Dio, ubi fup. (% 2) Idem ibid. (33) Peller. ubi fup. Tom. Troif. PI. CXXII. 11. (34) Joan. Vaill. ubi fup. p. 157. N n 2 feldom [ 276 ] feldom vifible on the Parthian coins. The reverfe agrees with that of the piece I am conlidering, in every particular but the infcription ; from which, tho’ Phoenician, that of the medal before me is in- ti rely different. That on M. Pellerin’s piece, howe- ver, is formed of lix letters ; the three firft of which are apparently Mem, Latnerf, Caph , which conflitute the word melec, king. The fourth greatly refembles the Chaldee Vauy and not a little one of the forms of the fame element (35) uied by the Palmyrenes. The fifth mull be taken, as I apprehend, for Rf/ch, being very like the figure of that letter on the medal engaging my attention here*. The fixth may pafs for a form of D.aleth , that has buffered from the injuries of time. Admit this, and I fee not the leaft impropriety in fuch a conceffion, and the word maybe read orod ; which, flripped of the Greek termination, is not only a Parthian proper name, but the very name of the prince who fat upon the throne when (36). the Parthians were poffeffed of Cilicia, and their forces overthrown by Ventidius.. Had it not been for the fuppreffion of the latter Vau9, this word would have been intirely the fame with vorod, or orod, exhibited by three Palmyrene (37) inscriptions, and written TOPOAHE, vorodes, or orodes, in the correfpondent Greek ones. And with regard to the fuppreffion of Vau3 this was by (35) N uni. (?.6) (37) Philofopb. Tranfufl. Vol. XLVIII. p. 603. & Tab. XXX. 3* Appian. Alexandria & Dio, ubi fup. Philofopb, Tranfotft, Vol, XLVIII, p. 694, 695) no [ 277 ] no means uncommon amongft the Phoenicians, as I have : el fe where (38) inconteftably proved. If the interpretation of this fhort infcription now laid down fhould meet with the approbation of the learned, it would bring no fmall acceflion of ftrength to the notion here advanced. It would alfo evince, in conjunction with what has been offered, beyond the poffibility of a doubt, that inferiptions of very different kinds have been handed down to us by this fpecies of coins. That medals fhould have been emitted from the mint at Tarfus with Phoenician letters upon them, to thofe verfed in this branch of literature can be no matter of furprize. It has been proved, that fuch pieces as that now in view were (39) If ruck by the Phoenicians, fome of whom were undoubtedly fettled at Tarfus, and confequently ought to be deemed Phoenician, not Punic, coins. As the medal itfelf, according to the gentleman who purchafed it in the Raff, feemsto have been found either in the neighbourhood of Plems, formerly denominated Emefa (40), or fomewhere near Efbele, or Gibele, the Byblus (41) of the antients, and confequently at no very great didance from the borders of Cilicia 5 my explication of it may podibly, I would flatter myfelf, prove not altogether unfatisfadtory to tile- learned. To what has been here advanced fome may per- haps objedf, that we can difeover little of the Par- (38) Philofopb. Tran fa cl. Voi. L1V. p. 419. (39) Peller. ubi fup. Tom. Troif. p. 162, 163. (■40) Poc. Obfrvat, on Syria, p, 98. (41) Id. ibid. thiaii I 278 ] fhian tatte or genius in the coins I have been en- deavouring to throw fome light upon. They may tell us that fuch pieces Teem much more to refera- ble the medals of Syria and Phoenicia than the Par- thian coins. To which I would only beg leave to reply, that I confider them rather as pieces ftruck at Tarfus by a Greek or Phoenician artift, in fome part of the fmall fpace of time that the Parthians were matters of Cilicia, than as proper Parthian coins. This appears to me, I own, extremely pro- bable j but that it was an abfolute fadt, I mutt: not take upon me to affirm. Thus have I endeavoured to render it probable, from a furprizing concurrence of circumttances, and a wonderful coincidence of fadfs, that your Lordfhip’s Phoenician coin was ttruck at Tarfus, the capital of Cilicia, when the Parthians were matters of that country, about forty years before the birth of Christ. Whether or no the credi- bility of fuch a notion has been here fully evinced, your Lordfhip, whofe profound erudition, as well as ttngular humanity, is fo well known to the whole learned world, with your ufual candour and impartiality, will decide. Be this, however, as it will, I fhall offer no other apology for any miftakes or omiflions that may be difcovered in this paper, than that I have been obliged to tread unbeaten paths through the whole courfe of it ; an explication of the medal in quettion having, as I apprehend, been hitherto unattempted by any confiderable writer. I might have expatiated more largely upon the prefent fubjedt, but am afraid your Lordfhip will think me already too prolix. [ 279 ] profix. I (hall therefore at this time only beg leave to add, that by honouring me with your future com- mands, to which the greateft and mod ready atten- tion (hall ever be paid, you will confer the highefl: obligation upon. My Lord* Your Lordfhip’s very faithful. and mod; obedient humble Servant, Chrift-Church, Oxon. April 25, 1767. John Swinton. Erratum, in Philofophi TranfaR. Vol. LIV, Page *■ 139* note, 1, 2. for read VC?> or ScbinyTxade * XXX. Re- XXX. Remarks on the very different Accounts that have been given of the Fecundity of Fifes, with freff Obfervations on that SubjeSl : By Mr. Thomas Harmer ; com- municated by Samuel Clark, Efq\ F. R. S; Read May 28, K g H E afcertaining the fecundity 1 of the feveral fpecies of ffih, as far at leaft as we are able to do it, is one point ne- ceffary to the making our natural hiftories perfect ; and at the fame time opens a view wonderfully af- fecting to the imagination. The carp, in which Petit is faid to have found 342,144 eggs; and the cod, in one of which of middling iize Lewenhoek, it feems, affirmed there were 9;3 84,000, have been mentioned as very furprizing inftances of this fecun- dity ; and by their being fele&ed by writers, who appear to have been well verfed in this part of learning, they ffiould feem to be the mod memora- ble we have of this kind. The accounts, ’however, that have been given of the friii tfulnefs of thefe two fpecies of ffih differ from each other very confiderably. For Brad- ley, the Botanic Profcffor at Cambridge fome years ago, tells us in his philofophical account of the works of nature, a book proffffedly writ- ten on a very celebrated, though unexecuted [ 28, ] plan *, that the increafe in Tome fifh is furprizing, and to thofe that are not ufed to difquifitions of this kind muft appear incredible j he however links the number of eggs in thefe two fpecies extremely, when he tells us the roe of a cod-fifh mull contain about a million of eggs, and that a carp does not fpawn lefs than 20,000, to which he adds, and perhaps a. tench half as many. This is making the cod almoft ten times lefs prolific than the other account, and the carp above feventeen times lefs. Some other writers, who appear alfo to have been defirous to imprefs the mind with the wonders of natural hiftory, have made their eftimate {till lower. One of them, I remem- ber in particular, in one of our monthly publications, from whence numbers muff take their ideas, who have no opportunity of reading more authentic ac- counts elfewhere, tells us, that carp and perch have nine or ten thoufand eggs, and that cod-fifh, and heriing, are not lefs prolific ; and this he calls wonder- ful. The increafe of cod-fifh is indeed, even accord* ing to this, very great, but almoft a thoufand times leis than Lewenhoek is faid tohave found it. Their accounts being fo very different, I thought I fhould n-ot improperly employ lome lei fu re hours, if I inquired into this matter afrefh, and law what the fecundity of thefe. fpecies of fifh really was, as well as of luch other forts as - might fall in my way ; and efpecially as I had found that a finall pickerel, vvhofe fpawn I had taken a pretty exadt account of, from mere curiolity, fome time before, contained no fewer than 25,800 eggs: a fifh which. * Propofed by. 3Vfr, Addifon in one of the Spectators. Vol. LVII. O 0 nonee t>82] none of thefe authors had mentioned, and of which notwithstanding a fmall one had produced a larger number of eggs than Bradley himfelf had aflignsd to the carp, which has been always looked upon as ■remarkable for its prolific quality, not to mention the unknown writer, who makes its fecundity much lefs. The make of my eyes, which are much lefs proper for diftinguifhing objects at a distance, than the feeing fmall things that are near ; and my living in a mari- time country, and though not near the fea, yet in a fituation which I thought very proper for the pro- curing fuch fifh as I wanted, were additional motives to the fearch : though as to the laft particular, I have fince found myfelf greatly difappointed. It will not he imagined, that, in order to afeertain the real number of eggs in each fifh which I exa- mined, I told them all over one by one; this would have been, if not abfolutely impracticable, at leaftin- confiftent with other engagements, and much more fatiguing than was necefiary. My way was to weigh the whole fpawn very exactly ; then to take a piece weighing twenty, thirty, or forty, or more grains, as was mod: convenient, and after weighing that parcel with care, and giving the turn of the leales to the weights, not to the eggs, to tell them over very carefully ; and then by dividing the number of eggs by the grains, to find how many eggs there were in each grain, or nearly fo. I fay nearly, for there mud, according to this method, have been rather more ; but I chofe to eftimatc them after this manner, that there might be no danger of reprefent- ing the fecundity of thefe animals greater than the truth [ 2-8 3 ] truth. I frequently boiled the portions of fpawn that I told, and after macerating them fome hours in water, gently prelied them with a penknife, whofe point I afterwards made ufe of to number them diftindly, by feparating them from each other to greater diftances, after they were rendered by that gentle fqueezing fitter for telling over. In feveral filh I found their eggs of very different fizes. In fuch cafes my rule was, to tell all I could difhnguifh by my naked eye, and thofe only y though I have often found, by the help of an eye-glafs, that, by thus limiting myfelf, I palled over great multitudes of eggs that might juftly have been counted*. I generally told them on a fine earthen * For, though they were very different in fize, they were all, I prefume, to be depofited in the proper places for hatching that feafon, though it may be not on the fame day, fince after fiftv are Ihotten, as it is called, we find no eggs at all in them. I think I do not by any means take upon me to affirm, that all fifii depofite their eggs after this manner, i. e. by degrees, and at times a little diftant from each other; but fome fpecies of them, I fhould think it is plain, do. This is t^ecafe of ftickleback in particular, in which, when they have been extremely diftended with fpawn, I have found feveral eggs very large, but feveral hun- dreds very fmall, and many of them too fmall to be counted diftindt- ly by an unaffified eye, which fmaller ones could never, I appre- hend, grow to the fize the larger ones had grown to before thelarger ones were excluded. 1 have feen fome of thefe eggs fo large, that 24 or 25 would weigh a grain ; about which fize, 1 believe, they are excluded, fince fome of that bulk came away from one of thofe creatures after it was taken out of the water,, and were found in the paper in which it was wrapped up: but generally upon opening thefe fifh they are not quite fo large, though very large in comparifon of many of the reft. I told in one of thefe ftnalleft of fifties, which weighed very little more than 14 gr. fpawn and all, about 936 eggs, fome of which almoft eluded my eye, befides O o 2 veflel* C 28+ ] vtflcl, which was extremely black, by which means I could much better difeern them, than 1 otherwise fhould have been able to do. The weights 1 have reckoned by are Avoirdupois weights ; but there being no weights of that fort lmali enough to aniwer ail ptirpoles, I was obliged to make ule of grains along with them, of which I reckon 43 yL. make an ounce Avoirdupois. After this manner i made the cbfer- vations of which I am going to give an account, with ail the nicety and care J was capable of. 1 begin with the herring, which makes a diftin- guifhed figure in thefe two counties of Norfolk and Suffolk, and a confiderable part of our commerce, when faked and fmoked. One of the above-men- tioned authors fuppofed, they may have 9 or 10,000 eggs : of feveral 1 examined, I found none which had lo few as 20,000 ; and in one I found 36,960. The intermediate numbers which appeared to me on numbers of others that I could not tell at all. Thofe that I told were of all fizes ; and though there were but 56 very large eggs, yet the creature was extremely didended. Now it does not ap- pear poflible that all the 936 eggs fhould grow to the hulk of the largeft of their companions without deftroying the fifh, fince the growing of 56 to fuch a fize as to weigh about i| grain diffend • cd it in fuch a manner as I have hardly feen in any other fpccies of fifh. In fome very large fticklebacks, which weighed 45 or 50 grains, I have found between ?. and 300 of thefe large eggs, along with great numbers of fmaller ones, lo that the number of large eggs feems to bear fome proportion to the fize of the fifh, by which means a greater number of eggs, anfwerable to their fize, may be depofited in the fame time in which the fmaller fifh of this fpecies difeharge their lefs numerous fpawn. I will only farther obftrve here, that if this be the cafe as to the other fifh, the number of their eggs may, on this account, appear very different to different^obfervers.^ examination. C 285 ] examination, may be met with in a table that I fhali place at the end of this paper, which will give the particulars relating to this lort of fifh,‘ and feveral others, in the fhorted manner, but with fufficient didindnefs. The next that came under my infpedion was the fmelt. Thefe, it is well known, are a very fmall lore of fifh, and are frequently ufed for garni lla to thole that are larger. In one of thefe, which did not wewh quite two ounces, I found 38,272 eggs ; and in none fo few as 20,000; excepting one, which was ex- tremely fmall, not weighing above 289.1. grains, in which very fmall fifh I found 14,41 1! This was amazing. I was much more furprized, when, after this, I learnt what was the fecundity of mackarel. This no author that I met with gave an account of, though it is a fifh fo extremely common. In one large fifh of this kind, weighing fomewhat better than 14th, I found 454,961 eggs; in a fecond, of much the fame weight, 430,846 ; and in a third, which weighed but about itt>2oz. I found 546,681. I was adonifhed upon this, that Bradley fhould call the fuppoled fecundity of carp, which he makes to be but about 20,000, fo furprizing ; or that even Petit’s obfervation, which made it appear, that in fome filh of that fpecies the eggs amount to 342>J44> fhould caufe the carp to be feleded as the mod: extraordinary fifh for increafe, after the cod, when it appears to be fo much greater in mackarel (which is at the lame time fo common a fifh), as to be not much fhort of the proportion of 5 to 3, in the lad I examined. I fhali [ 286 ] I fliali leave it to the table at the clofe, to give an account of the prolific quality of fome other fi!h, whole eggs I have counted, and (hall pafs on to what I have found in the carp, which fpecies Petit ex- amined. As to this fiih, though I cannot fay I have found the eggs, in thofe that have come under my notice, fo numerous as he did; yet, as I have found the number much larger than Bradley mentions, fo I make no doubt but that Petit really found them amount to 342,144 ; and I would add, that I dare lay they may be found to be much more numerous ftili in large fifin of this kind, fince in one that I examined, weighing but i6±oz. I found 101,200; and in ano- ther, which weighed no more than 25I0Z. I found 203,109, and carp grow to a much larger fize than the biggeft of thefe, but I could not procure any of thofe large carp that were full of fpawn. If I failed in verifying Petit’s number of eggs in a carp, I found thofe of a tench to exceed it, more than once, which Bradley reckons not to produce more than half the number a carp does, or 10,000. For I found in one tench, which weighed 21.1b-, 383,252 eggs at leaf}; and in another that weighed not quite il.lt>, 350,482. As to perch, which one of thofe authors I men- tioned puts upon a par with carp, I could get none of any fize. The large!}, which weighed but 8 oz. 9 dr. contained 28,32 3 eggs ; and a fecond of 5 oz. 10 dr. had in it 20,582. They feem, however, to be much lefs prolific, in proportion to their hulk, than tench, fince the large!} of thefe had but about 28,323 eggs, and I found a tench of nearly that fize, weighing but 8 oz. 14.* dr. produced 83,104. Bradley C 287 ] Bradley Teems to have been as careful not to be guilty of exaggeration with refpedt to the cod-fifh, as in the other cafes. He e ft i mates them at a million) while Lewenhoek affirmed that he found above nine millions of eggs, in one of middling fize. The fpawn of one of that fize which I examined, that is to fay, one of 18 or 20Tb weight, I found to contain between three and four millions, if my friend’s weights were accurate, for I made the examination at a diftance from home ; and by a fubfequent obfer- vation at home, I have reafon to think there was this number in it, though I was prevented purfuing my fecond examination fo far as I would have done, bv fome particular occurrences. According to this, there is nothing incredible in Lewenhoeck's account; his fifh, I fuppofe, being remarkably diftended with fpawn, and for that reafon perhaps thought, by that inquifttive and curious perfon, a fubjecft that ought not to pafs unexamined. I have hitherto mentioned no flat fiflh, nor do I remember that any author has given us an account of their fecundity. I imagined, from their make, it could not be extraordinary; I was therefore extremely furprized to find in the firft flounder I examined and which did not weigh quite three ounces, 133,407 eggs; in a fecond, which weighed little more than 34 ounces, 225,568; and much more ftill when 1 difcovered in a large one, that weighed about 244 oz. and which was of that fort that is lpotted like a plaife, as Ray has told us fome flounders are, 1,357,400: this was truly aftonifliing. The number of eggs that a foal produces, I have cbferved to be great, but nothing like that which I 6 found [ 288 ] found in flounders, finding in one, which did not fall much fhort of a pound, rather more than 100,000; and in another, that weighed about five ounces, 3 8>772- To make this difquifition hill more extenfive, I examined two or three kinds of fhell-fifh. 1 found in a lobfter of 144. oz. when in the fliell, and of 104, when diverted of it, 7,227 ; and in another that weighed 2±lb, and out of the fliell fomewhat better than i.l lb, 1 told 2 1,699 eggs. I took alfo the pains to tell all the eggs of fome fhrinips, one by one, and found in one which weighed 17 L grains only, 3057; in another of 31 gr. 4090. ; and in a third of 39 gr. 6807. This, confidering the fmallnefs of the creature, is more remarkable than the fruitfulnefs of the lobfter ; but neither is the one or the other to be compared, in this refpeft, to the crab, for in a large one, weigh- ing near 1 lib, but not quite, I found that the fpawn weighed 687 gr. but the eggs were fo minute, and at the fame time adhered fo clofe together, that I could not number them diftindlly ; however, the weight of rhe whole, and the minutenefs of the eggs, fliow that they mud have been very numerous; and I believe from a rough eftimate I made, that they exceeded a million. ' ? The table, at the clofe,. gives all thefe ac- counts,' with the addition of feveral more particulars, in a very fhort compafs. The fir ft column contains the names of the fifh which I examined ; the lecond theirweight; the third the weight of their fpawn; the fourth their fecundity ; and, as I fuppofed fome perfons might be defirous to know how large a portion C 289 ] portion of fpawn I weighed in each cafe, I have fet down the number of grains in each fuch portion, in a fifth ; the number of eggs found in a grain, by this method is feen in a fixth, by which we may give fome gu.efs at the different fixes the eggs of each fpecies are of, when they are excluded ; and I have made the time of examining each fifih refpedlively a feventh ; which pofiibiy may be of fome ufe to thofe who may have an inclination to repeat any of thefe obfervations, as from thence may be learnt fomething concerning the moft advantageous time of examining thefe creatures, which certainly ought to be as nearly as we can, when the eggs are come to their full fize,. , and before any of them are depofited. However, after all, if my notion is juft, that fome fpecies depofit a part of their eggs come to their full growth, before others laid the fame year are big enough to be told with diftindtnefs, the accounts of the fecundity of fuch fi£h muff be extremely defective y and this I apprehend, amongft thofe I have examined, is the cafe of mackarel, carp, tench, and fome others ; in herring, &c. there does not appear fuch a difference in the fize of different eggs-. From this table it appears, that the fize of the eggs is nearly the fame in great and fmall fillies of the fame fpecies, at the fame time of the year ; that the quantity of fpawn is, ufually, nearly proportionate to the fize of the animal, from whence we may give a tolerable guefs at the greateft fecundity of each fpecies, if we know to what weight they have been found to grow while in a breeding ftate ; we may likewife fettle their produce at a medium,, upon learning what is the mean fize of each fpecies Vol. LVII. Pp when [ 290 ] when in the forementioned ftate, but we fee, however* that this is not univerfal, nor confequently perfectly exadt, Tome fifh being much more prolific than others of the fame fize, and fpecies. To conclude, the great fecundity of fifh is not the only thing that affects the imagination, when we are examining matters of this fort : the extreme difpro- portion between their fize when they firft appear in the water after hatching, and that of their full-grown ftate, as well as the little proportion that is to be obferved between the bulk of filh of different fpecies and that of their eggs, are things that are very amazing to perfons of a curious turn. The egg of' a fmelt, which at its full growth weighs but two or three ounces, appeared, in thofe I examined, to be larger than thofe of a cod-fiffi, which weighed eighteen or twenty pounds, and might have grown to double that bulk j and that of a fticklcback, which is the fmalleft of all known fifh, was found to be above fix times bigger than the largeft I ever obferved in a fmelt. What becomes of fuch amazing numbers of young fifh, and why fome are made fo extremely prolific, the flounder and crab in particular among the fmaller forts, would doubtlefs be highly entertaining fubje&s, if duly illuftrated ; but thefe are enquiries I have no opportunity of making. The [ 29I ] The TABLE. »f i Names of the fifli. . 2‘ . , ( Their weight . 3- vv eight o' Jie fpawi 4- Tecundit) The port ion of'fp. weighed 6. N°.ofeggs to a grain /** * Time of exam. oz. dr. grains. grains. rP N°. i l6 1 2 i 265 ior.200 46 80 May 25 N°. 2 2 5 8 2571 203. 109 55 79 April 4 d-fifh — 12.540 3.686.760 29 i 294 •> Dec. 23, ounder N°. i 2 14 iS2-| • I33-407 23 731 Feb, 21 N°. 2 3 SI I52 225.568 19 1484 Dec. 18 n°.3 6 12 598 351.626 26! 587 March 14 N°. 4 24 4 2.200 1.357.400 24l 617 d°._ rrring N°. i 4 3 367 32.663 48 89 Oa. 8, 176' N°. 2 5 2361 21.285 4«i 90 29 N°. 3 3 13 259 23.569 522 91 Oa. 2, 176^ N°. 4 5 IO 480 36.960 53 77 25 5 4 6* 366 29.646 57 8r d0.. N°. 6 ' 4 8 420I 27-753 5* 66 . Nov. 3 . N°. 7 5 1 49cf 32.863 4If 67 oa. 18 )bfter N°. i 14 8 7227 14 April 4 N°. 2 36 0 1671 21.699 129 Aug. 1 1. ackarel N°. i 20 — 1027 454.961 33 443 June 20,176 N°. 2 20 — 949 430.846 24! 454 29 n°.3 18 — 1223I 546.681 32I 447 18,176 :rch N°. i 8 9 765f 28.323 85 37 April 5 N°. 2 5 10 502 20.582 85 41 t> ckerel N°. i 56 4 5ioo| 49 304 70 9x April 25, N°. 2 3248 80.388 76i 24? Nov. 25. N°. 3 48 10 j 31 84 33-432 43 iof. March 19. awn N°. i (127 gr.) 3.806 243 May 12 N°. 2 (94i gr-) 3479 287 d°. N°. 3 (ioo§ gr0 3-579 247 d°. Road [ 292 ] I, 1 i l. 3* 4* 5* 6. 7* Ties of the fifh. Their weight Weight of Fecundity The portion N°. of eggs Time of exam the fpavvr of fp. weighed to a grain oz. dr. grains. grains. April 4 (or what' N°. i 2 — 1 14 9.604 to be of lecies) In°. I N°. 2 3 6 3 8 8 67 1 3464 43 6i5 29.799 68 42I 65 8b May 4 176; d°. N°. 4 2 2 153 9.486 42I 62 5 N°. 5 10 6 1 361 81.586 39 226 2 176 N°. 6 9 iof 417 n 3.841 42 273 6 N°. 7 3 8 21 31 45-475 20 213 24 p (with a N°. i (i7fgr-) 3. 3,057 1000 May 3 10 coloured N°. 2 (39 &•) 7 6.807 972 d . •) J N°. 3 4.601 d°„ (with 1 N°. 1 (3l gr.) 5 4.090 818 d°. olour) j N°. 2 (22 grO 4 2.849 712 d . N°. I 2 - ■ - 149I 38.278 3° 256 Feb. 21 N°. 2 (289 |gr-) 5° 14.41 1 288 Mar.21,1764 N°. 3 I 14 157I 29.925 4 of 190 27^761 N°. 4 I 12 145! 30.991 20 21 3 28 N°. 5 1 7 149 24.287 20 163 d°. N°. 6 I 5 136 23.800 20 1 75 d°. N°. i J4 8 S47i ico.362 20 >85 June 13 N°. 2 5 — *79* 38.772 20 216 28 \ N°. I 40 383.252 * ■ — - — May 28,1764 N°. 2 28 8 533§ •280.087 2 5 525 3^76i N°. 3 8 I4| 224 83.104 20 37 1 10 N°. 4 9 8 2844 108.963 20 383 d°. N°. 5 12 8 366 138.348 42| 378 d°. N°. b 27 9* 1969 350.482 23 178 June 1 1 N°. 7 14 J5 866 1 38.560 20 160 d°. 5°. i . of the tench certainly had a much larger number of eggs ; but being extremely diftendec pawn, and unluckily let fall before it was brought to me, the enveloping fkin in which the vere contained was broke, which made it difficult to determine fome circumftanccs relating ; fifh ; it however had the number of eggs 1 have fet down, at the lowed way of reckoning. believe many thoufands more. . . ive taken no notice of fcveral frs^lions in the number of eggs contained in a grain in many choofing to fall rather below than to exceed the truth, in all the fifh I have given an account this table. I have been fcrupuloufly exad in all particulars, excepting what are contained ill ond column, which gives the weight of the fifh 1 examined, in which the utmeft nicety wa< c c fTa , y • fome few might weigh a little more or a little Ids ; bat all were nearly of the : fet down, and much the gr cate ft part exa&ly fo. ' XXXI. An [ 293 ] XXXI. An Account of an Hydro-enterocele , appearing like an Hydro-farcocele , and ending in the Death of the Patient ^ in which the Inteftine had paffed fro?n the Hernial Sac , into that of the Hydrocele by which the Strangulation was formed. Com- municated by Mr. Le Cat, F. R. S. & c. in a Fetter to Charles Morton, Sec. R. S. Iranjlated by J. O. Jufta- mond, Surgeon . Read May 28, ^ N the year 1751, I prefented to the 1767 * jl Royal Society an obfervation of a rup- ture, which had two hernial facs ; at prefen t, I have the honour to fend them the hiftory of another kind of rupture with a double fac, much more fallacious and dangerous than the former, lince I found myfelf deceived by it, after the experience of forty years. James Philip Chiquet, aged 65 years, of the Parilh of St. Vivien at Rouen, was admitted into our hofpi- tal on the 24th of January 1767. The account, which be gave of himfelf, was* that he had been accuftomed to a rupture, which he had not been able to reduce for a fortnight part, and, that lince eight days he had been feized with a vo- miting, and was incapable of taking any nourilh- ment. [•294] ment. Upon examination, the tumor was foft, es- pecially at the upper pa; t towards the ring, which teemed to be fo free and difengaged, that the finger with the integuments might be pufhed under it : the large cord, which came down to it, was flat, foft, and. appeared to be compofcd entirely of the Sper- matic vcfiels enlarged. r # O i l)e extremity of the Swelling, which was of the fize of a large orange, was evidently a very transpa- rent hydrocele; at the baits of which Some hard points were to be felt, which I thought to be fchirrous tumors. I concluded, therefore, that his complaint was an old hernia, Succeeded by a lar- cocele and an hydrocele, and that the inteftine was at that time returned. I imagined that the vomitings, which were not frequent, might be caufed by Some other diforder, perhaps by the progrefs which the farcocele might have made in the cavity of the ab- domen ; and Ialfo thought that the weak and almoft dying ftate he appeared to be in, was a prognoftic of the fatal manner in which thofe cales ufually termi- nate; for his ftrenglh was fo far exhaufted, that he expired in the following night. 1 was very defirous of examining the cafe, having been always induced to fulped, from the vomitings, and the flatnefs, foftnefs, and fize of what pafled through the ring, that there was a defeent of the inteftine. See Tab. XIII. Upon opening the common hernial he, a. b. b. a large portion of inteftine, c. d. e.f g. pre- sented itfelf, which w7as very flaccid and almoft empty; but what Surprized me moft, was, to find that thecon- voluted ( [ 295 3 yoluted extremity, h. i. k. of this inteftriie, had iniinu- ated itfelf into the lac, /. in. n. rotundaveram, eae zonae arcuabantur in femicir- culos ab indufiis extrorfum prominentes magis, quam zonae parallels lateribus j quamquam hae etiam finuabantur introrfum ubi indufiorum latera vitris non adhaerebant. Sed de his alias plura, nec, ut arbitror, inutilia; funt enim hae zonae veftigium confpieuum eledricitatis fe effundentis circa limites redilineos, arcuatos, acutos, &c. XVI. Vitra quum cernebam omnino eledrica, dimo- vebam a catena, attredabam in extimis indufiis, fiebat explofio, quatiebar, neque interea ab ex- plofione mutari animadvertebam coloratas zonas indicia cohaefionis. XVrII. Re enim vera obniti debebam valide admo- dum, ut vitra memorata disjungerem; quam primum vero hanc disjundionem me affequi fen- tiebam, evanefeebant zonae coloratae ; intereaque fcintillae, crepitus, lux, & phenomena exiftebant omnia, quae memoravi (XIV), imo iis alacriora. XVIII. Porro fi vitra disjungerem anteaquam attrcc- trando extima induiia explolionem cierem, vitrum fuperius apparebat utrinque eledricum excedu, inferius utrinque defedu : Si deinde explolionem conbcerem, a disjundione, quae poltea fiebat, mutatae apparebant eledricitates ; vitrum fuperius erat utrinque eledricum defedu, inferius exceflu. XIX, Si vitra poll: explofionem disjungere, 6c con- jungere pergebam, quemadmodumin fuperiorc ex- perimento, eaedem, quae in illo, imo vividiores confequebantur eledricitatum ofcillationes, qua? jQmiliter penicillo expendebam, 6c ftellula. XX. Neque [ 3°5 3 XX. Neque hie deerat vitrum praspollens, quod aliam componeret ex fua inverfione cum ea ofcil- latione eledricitatum ofcillationetn. Hasc una erat, ipfaque aptiliima differentia : Vitrum praspollens in fuperiore experimento illud erat, quod unum fiebat eledricum a catena. At in hoc experimen- to, in quo ambojundim fiebant eledrica, praepol- lebat vitrum tenuius d, five ipfum catenam tange- ret, dum fiebant eledrica a catena, five effet in- ferius, & communicaretcum foio. XXI. Praspollens vero vitrum hoc fuam vim prim© demonftrabat in explofione, quas tentaretur in duobus vitris feorfim : fcilicet li pod explofionem jundorum vitrorum intimis faciebus disjundorum aptabam indufia, vitrum praspollens me quatiebat mediocriter, aliud non item. XXII. Itaque li, quemadmodum in fuperiore expe- rimento, ita hie pod explofionem invertebatur vi- trum puspollens, eledricitates a disjundione, et conjundione exidentes mutabantur fimiliter in contrarias, redituendae redituto vitro praspollente, iterum mutandae eo iterum inverfo, neque mutandis inverfione vitri alterius fola. XXIII. Atque hanc hujus fuas vis tenacitatem per- gebam adhuc aliter experiri in vitro praspollente. Duo vitrajundim eledrica a catena datim divelle- bam, qua prima in disjundione fcintillas, lux, crepitus, phenomena obtingebant omnia iis fi- d PI ura in his experiments adhibui vitrorum par ia, & Temper turn in hoc, turn in experiments, qute fequuntur, illud pias- pollebat, quod erat tenuius ; nunc in par vitrorum incidi, quo- rum alterum, quod prtepollet, craflius vkleiur, fed videtur etiam denfitate minore. Vol. LV1I. R r C 3°6 ] milia, quae memoravi (XIV) • turn induebam in- ti mas eorum facies, vitrum prsepollens attredabam, quatiebarj confummata explofione ipiflm ap- tiffime attredabam (XIII), pod minutum tempo- ris aptabam vitro focio, quod interea pependerat in aere fummo angulo fufpenfum ; junda attrec- tabam, vix exidebat explodoj disjunda eledrici- tates mondrabant iis contrarias, quas folent oden- dereante explofionem. Atque turn a disjundione, conjundione confuetas pod explofionem eledri- citates ofcillabantur ; idceque invertebantur inverfo vitro praepollente. XXIV. Vitra eadem jundim eledrica tentabam, ut exploderent junda, deinde fejunda, iterum I unda, iterum fejunda ; podea attredabam du- ll u til feorfim fingula (XIII) ad minutum tempo- ris, iterum junda eadem, qua principio fuerant, podtione, pod debitam moram, & attredationem, eledricitates demondrabant fingula contrarias dec- tricitatibus ante explofionem ; & turn etiam ab inverfione vitri praepollentis ex eledricitates abibant in contrarias. A ExPERIMENTUM TERT1UM. XXV. Duo vitra A & B fingula rite induta fingulis catenas ramis objiciebam, ut fierent feorfim elec- trica; atque, ut sequilibratas eledricitates ferva- rent, quales nempe eodem tempore a catena ca- dem immitti potuerant, ea cautione a catena ipfa dimovebam, ut neuter ejus ramus cum folo com- municaret nifi pod femota vitra ambo. XVI. Mox [ 3°7 ] XVI. Mox denudatis duabus imis vitrocum faciebus, (quod dum fiebat, fcintilluhe exiftebant lingula? ex fingulis imis vitrorum faciebus) aptabam vitrutn alterum alteri, ut faciebus denudatis le mutuo con t inherent ; atque turn nec ex attredatione ;ex- timorum indufiorum ulla exiftebat explolio, nec ullam percipiebam cohaefionem in disjundione-: fejunda, atque iterum induta quatiebant valide admodum, fed tenuius validius j iterum junda faciebus iifdem denudatis dudum attredabam, co- hieiio obtinebat aliqua ; disjungebam, & tenuius, quod praepollebat in fuperiore experimento, in hoc item erat praepollensj ipfum ab hac disjundione eledricum defedu apparebat utrinque, & vi- trum focium apparebat utrinque eledricum exceffu, inverfo vitro tenuiore, eledricitates. a con- jundione, & disjundione ibant in contrarias, in- verfo focio craffiore manebant eaedem. XXVII. Poft haec capiebam experimentum idem, fed denudabam vitrorum facies fuperioresp his junda vitra, nec quatiebant, nec cohseiionem monftrabant fatis manifeftam j fejunda quatiebant ambo, fed tenuius validius ; iterum junda dudum attredabam, atque turn a divullione vitrum te- nuius erat utrinque eledricum exceflu, ciaffius utrinque defedu j inverfo tenuioie, eiediicitatcs mutabantur in contrarias ; inverfo alio manebant eaedem. XXVIII. Porro in primo experimento vitrum, quod contrarias eledricitates acceperat in faciebus oppo- litis, quodque adeo habebat vim explodendi, ip- fum erat praepollens ; in experimento altero, quod fejundum ab alio, aut folum explodebat, aut ex- plodebat alio validius, ipfum erat praepollens. Idem r R r 2 conflat [ 3°8 ] conftat in tertio hoc experimento •, quod nempe vitrum explodit alio validius, ipfum, quam habet in interiore fua facie eledfricitatem, eandem de- terminat in facie fua exteriore, & contrarias deter- nainat in faciebus ambabus vitri focii (XXVI XXVII.) XXIX. . Pergebam experiri vitris iifdem limi-liter eledtricis a catena, fed unius fuperiorem, alterius inferiorem faciem denudabam ; hoc illi impone- bam, continuo cohasfio obtinebat aliqua ; attredta- tis extimis induhis, quatiebar, atque ab hac explo- none cohasfio invalefcebat ; divellebam, & attrec- tabam feorfim lingula vitra, vitrum tenuius qua- tiebat me mediocriter, aliud non item : jundta fa- ciebus iifdem contrariis cohxrebant aliquomodo. Quare cum in experimento hoc tertio aptantur al-~ tera alteri contrarias vitrorum facies, fimilia iis ob- veniunt, quae in experimento fecundo, ubi duo vi- tra hunt jundtim eledtrica. XXX. Cater um quales in fecundo, tales in hoc ex- perimento contingunt poll explohonem eledtricita- tum ofcillationes, praefertim cum experior, ut in num. XXIX. turn quae pendent a fola vitrorum conjundtione, & disjundtione, turn quae cum iis fefe componunt, &. efficiuntur ab inverfione vitri prtepollentis. XXXI. Vitri autem praepollentis (XXIX) vim aliter etiam experiebar. Pofteaquam jam femel fejundta adegeram ad explohonem, iterum jungebatn, turn iterum disjungebam, atque vitrum tenuius ite- rum indutum- explodebat aliquomodo ; quod dc- nuo, 6c tertio adhuc experiens aliquam adhuc per- tipiebam commotionem .* vitrum autem craflius, 7; quutn t [ 3°9 3 quum in ipfo fimiliter experiri pergerem, nullo me ' unquarn commovebat modo. Experimentum quartum. XXXII.' Hadtenus de vitris duobus ; pauca nunc ad- dam de uno. Vitrum rite indutum, & eiec- tricum a catena fummo prehendens angulo fuf- pendo, turn diverfa confedtor, quas exidunt phe- nomena, indufia attredlando, divellendo, divellendo digitis, aut divellendo ftaminibus fericis $ eaque omnia experior turn ante, turn pod explofionem, Itaque, fi alternatim attredlo indufia vitri eledfrici, alternatim ignem haurio a facie redundante,immitto in carentem &c copia ignis quaque attredlatione haufti, aut immiffi refpondet fummas capacitatis e indufiorum, et magnitudini elediricitatum abfo- lutarum refiduarum ; eaque lege ignis hauritur, 6c immittitur alternis his attredtationibus^ ut conticef- cat eledlricitas omnis in facie attredlata, revi- vifeat in facie oppofita. XXXIII. . Si indufia oppofita attredlo fimul ambo3 explofio fit.; in-tereaque indufia vitro adherent va- e Ceu fi indufium faciei unius vitri communicet cum uno ho- mine fejuncto a foil , aut cum duobus, aut cum.tribus fimiliter feiundtis, aut fi communicet etiam indufium faciei alterius cum uno, duobus, tribus, Jiominibus, aut corporibus aliis defe- rentibus : copia ignis, quae alterna quaque attre&atione immitti- tur in faciem carentem, aut hauritur a redundante, .proportione refpondet fummae capacitatis &c indufiorum chartaceorum, &• hominum, aut corporum aliorum, quae cum unay aut ambabus faciebus communicant; atque prout major eft lumma earum ca- pacitatum, minore attreefationum numero exhauriuntur abfoiutze cppofitarumiacierum-eledricitatcs, - fl'U illS t 3IQ 3 lidius ; & dum pergo attredare, explofio, & -ad- hcefio confummantur. XXXIV". Pergo nunc indufia divellere daminibus lericis, ut, li quam ipfa a divuliione habent ele- dricitatem, retineant ; atque ante explofionem facies quarque vitri ea cautione denudata eledri- citatem odendit fibi contingentem, indufium quod- que eledricitatem pariter refpondentem demon- drat, & fuae capacitati proportionalem f-; dico autem contingentes elecff ricitates, qua? datas faciei ante explofionein conveniunt ex theoria Frankliniana. XXXV. Si pod explofionem ftaminifcus fericis indufia divello, facies vitri ambae eledricitatem mondrant, contingentem faciei ultimo denudatae, indufia de- mondrant contraries j ipfafque iterum fuaa capaci- tati proportionales. XXXVI. Nunc indufia digitis divello ; qure res non facit folum, ut lentiri non pofirnt eledricitates in- dudorum, fed aliquam preeterea infert mutationem iis cledtricitatibus, qua? apparent in faciebus nudis, cum perdamina ferica indufia divello. Itaque ante explofionem cum digitis divello indufium unum, ambte facies eledricitatem odendunt eamdem, ct contrariam illi, qua? contingeret faciei ultimo de- nudatae. XXXVII. Sed pod explofionem cum digitis indufia divello, turn utraque facies eledricitatem demon- drat eamdem, fed contingentem faciei ultimo de- nudatae ; atque hilce in divullionibus indufiorum, qua? aut digitis fiant, aut daminibus fericis, ofcil- 1 Loquor hie dc . capacitatibus, quas habent indufia chartacea folaj etenim unice circa cas capacitates expcmis fum. lationes [ 311 ] lationes eledlricitatum aliquae facile ohfervari pof-- funt. Unam hie ego attingam, quae accidit in hac ultima experimenti hujus parte. Vitri, quod ade- gi jam ad explofionem, latus unum apprimo fto- macho meo, laeva prehendens latus oppofitum, turn dextera divello indufium inferius, continue pollice laevae admoto indufio fuperiori, exiftit fcintillula j divulfum indufium inferius iterum admoveo, fuperius fcintillam exhibet aliam, fed primae con- trariam ; iterum illud divello, iterum hoc fcintil- lat, uti vice prima; illud rurfus admoveo, rurfus hoc fcintillat, uti vice altera, &c. fcilicet, fi alter- natim divello, & admoveo indufium faciei defeciu elecftricae, in divulfione indufium fuperius accipit ignem, effundit in admotione ; fi divello indufium faciei, quae ante explofionem erat excefiu eledlrica, indufium aliud inter divellendum effundit ignem, accipit inter admovendum. Quae omnia penicillo, &c ftellula, aut motibus ele&ricis confirmavi. V XXXIII [ 3*2 ] XXXIII. Specimen Hiftoriae N at ur alls Vol- genfis . AuElore J. R. For Iter. fitimen agere poftim, neceflarium duxi quaedam circa loca 8c fitum locorum praemonere. Regio cujus hiftoriam naturalem fum defcripturus, eft inter gradum 52 & 48 latitudinis borealis, eftque lita ex utraque ripa fluminis Volgae; id flumen ad Sarato- viam circiter milliaris Anglici latitudinem habet ; at tempore verno, dum nives per univerfam Ruliiam diftolvuntur, aqua ingens incrementum capit, 8c non rarofeptem novemve pedes Anglicanos furgit, 8c turn temporis in ripa orientali per duorum triumve An- glicorum milliarium fpatium diffunditur, et ufque ad altiorem ibi infurgentem planitiem ingentis deferti late vagatur, prataque 8c filvas ibi foecundat. A menfe autem Maio ufque in Novembrem vel initia De- cembris, quo fcilicet tempore gelu conftringitur, flumen fenfim decrefcit. Omnis ripa occidentalis Volgae per plufquam 260 milliaria Anglica eft mon- tofa ; montes aflurgunt in littore a 30 ad 6oorgyas Rufllcas, quarum quaelibet eft 7 pedum Anglico- rum; inde duorum triumve milliarium Anglicorum fpatio a flumine, alia feries montium, paene ejuldem altitudinis procurrit, eodem tenore quo flumen : 8c in horum montium dorfo frequens eft ftlva pluri- mum ex pulcherrimis conftans quercetis ab ipfo iugo NTEQUAM de quolibet genere corporum naturalium circa Volgam horum [ 3*3 ] horum montium ingens plan! ties, protenditur, trcf ufque flumen Khoper (Choper) quod in Tanaiin influit nifi qua, hinc inde, rivis quibuldam dividi- tur. Omnis fuperficies harum regionum ledla eft ad duorum triumve pedum altitudinem, terra ad- modum nigra, pingui 6c ad miraculum ufque fer- tili ; fub ea nil nifi marga 6c lapides margacei cretaceive reperiuntur, ad ipfum ufque flumen Volo-a. Haec eadem ripa occidentalis innumeris interfedta eft convallibus, per quas rivuli 6c fontes, quorum pauci funt perennes, ex propinauis de- fluunt montibus. Inomni hac regione gramina 6c variae plantae primo vere ad duos trefve pedes ra- pidiflime crefcunt. Ingravefcente aeftu fenfim iiccantur herbae in vaftis campis, 6c dein ab incolis^ qui rari admodum reperiuntur, primo vere igni comburuntur, maximo regionis detrimento; quia humiditas ex folo expellitur, 6c terrae crufta ye- 3uti teftacea inducitur; ut taceam falia, quae hinc in hac ipfa terrae incultae iuperficie, nimia iunt, 6c hyeme certe frigus intendunt, aeftate vero nimiam procreant iiccitatem >. praeterea 6c totae filvae flam- mis vento agitatis non raro intenduntur 6c pereunt. maximo darnno regionis hujus adeo frigidae. Ripa orientalis Volgae plane novum orbem no- bis fiftit. Ab ipfo flumine per duo triave miiliaria Anglica littora cin&a funt pratis amoenifiimis, 6c filvis, fruticetifque varii generis : innumeri. rivuli ex Volga derivati, paludes 6c lacus, haecce grata interfecant. Dein iupra haec prata ad 30 pedum altitudinem colles Iunt afcendendi, ex quorum fummo vaftus campus 6c planities immenfa. ad-. Yaiki ufque ripas protenditur ad 130 vei 150. Vol. LV1L. S s milftaw . [ 3H )' milliaria Anglica. Solum in pratis cx argilla, arena, marga, & putrefadtis vegetabilibus con- ftat. Planities fuperior nil nil! mera argilla eft, & maxime tritici miliique ferax. In medio harum regionum eft planities arenis cooperata be ericetis, in qua ft vix ad pedis unius alteriufve altitudinem arenam eruere volueris, ingentem vim habebis aquae dulcis : praeterea innumeris in locis funt lacus aquae falfae, rivulique amarulentam falfam- quebabentes aquam ; imo be plures illic funt lacus qui ftratis falis muriatici 3 circiter pollicum craf- fitudine funt ledta, ad plufquam decern duode- clmve pedum altitudinem ; & ft hie inde rivuli aquae dulcis per valles quofdam defluunt, non tamen ubique aqua fupra terram fluit, fed faepius per arenas be margacea ftrata tranfit, & poft ali- quot demuni milliarium intervallum, denuo fluere incipit. Coelum his locis plerumque fudum be ferenum eft. Hyeme intenfiftimum frigus, multaeque decidunt nives, circa menfts Novembris finem be per Decembrem : at fine Martii vel initio Aprilis i'ubito, aeris temperie nives liquefeunt herbae ubi- que luxuriant, be brevi tempore ad cubiti altitudi- nem fuccrefcunt, be inde uno tenore aer ufque ad fummum be poene intolerabilim aeftum in- calefcit, adeo ut gradual 1034. thermometri Fahren- heitiani celeberrimus Lerchius Aftrachani obfer- vaverit : be ego circiter fub gradu 51 degens men- ftbus Maio, Junio, be Julio 1763 in thermometro de L.iiliano gradum 97 obfervavi, qui circiter cum 93 4. thermometri Fahrenheitiani coincidit. Praeterea id precor cuivis legenti fequentes ob- fervationes animo obverfetur, me non tarn voluble omnis ' ' [ 3rS ] omnis numeris pcrfedlam hiftoriam naturalem harum regionum fcribere ; huic enim operi, nec tempus breviflimum, quo in. iifdem oris mihi verfari contigit nec vires, ob reliquas mihi de- mandatas maximi momenti occupationes, nec ipfe parvus tenuifque, quod fcio ingenii mei modulus fuffeciftent ; fed potius primitias hiftoriae natu- ralis, me^ orbi erudito, ea qua par eft animi mo- deftia, ofrerre. Naturae fequar ordinem in exponendis rebus ; ab inanimatis, ad vegetantia indeque ad viventia procefturus, in plantarum denominatione in anima- lium difpofitione ceieberrimi Linnaei editos libros, methodumque undique receptam, adhibiturus fum. Regnum Minerale. (A.) TERRAE, A. Argilla. a Colons luteu Omnis regio trans Volgam,. quam late defertum inter Volgam Gaikum, Samaram & mare Cafpium patet, nil nift hu~ jus generis argilla eft, at tritici miliique feraciflima. Eadern argilla bine inde & ex hac parte Volgae reperitur prope Saratoviam, prope coloniam Palatinam, ut & prope co- lonias ad rivulos diet os Lejhoi Karamyjh. Sosnofc 7, Tlajla , & Koola lynka. (3 Coloris rubicundi , particulis ferri impraegnata prope Volgam ad rivulum Cbmielojka , ut circa Tarty ki minoris ripas trans Volgam. * Sell,. menfe Maio ad initium Sept. 1765. S S 2 Rbomr [ 31-6 ] y Rhomboidalis lamellofa lutea. Haec argillae fpecies in torrents qui Saratoviam urbem trans- it, in determinate profundo reperitur. $ Rhomboidalis lamellofa nigricans . Tad a mol- liflima pinguis 6c laevis iub argillae num. y. memoratae ftrato invenitur eodem in loco; cum acidis effervefeit, 6c plurima teftacea inea reperiuntur. b. Marga. jo, Viridefcens. , pinguis , in colonia Palatina fub humo nigricante, reperitur maxima in copia. /3 Marga cinereo albicans cretacea, ibidem eodem in locoefFofta. c. Creta. Circa villam Zolotoi prope Volgam reperiunda; incolae ea utuntur ad dealbandos parietes. D. Humus nigricans pinguis. Cis Volgam omnis late regio a Penfa urbe ad Tanais viciniam ad duorum triumve pedum altitudinem hac humo teda eft : 6c uti facile ex adfpedu dijudicari poteft, orta eft ex vege- tabilibus per innumeras annorum feries, in his locis quotannis putrefadis. f. Terrai minerales. a Arena martialisy prope Ylafiam in vicinia Ca- nalis ab Anglo Perry eftofli, ad jungendumTa- na'im Volgae, item p rope Medveditzam , eamque influentes rivulos Ter Jam, Dobrynkam, 6c Bur Ink. '/ - 1 (3 Terra fale& he pate fulphuris mixta in fundo lacus Yeltonienfis fall], faepe inter ft rata falis reperitur. Argilla [ m 1 y Argilla fale communi impraegnata. Cis"Vpl- gam prope Saratoviam, ad montes j^Gcipitrino5 (fokolowe gori Igo) & trans Volgam in ripa minoris Tarlycki &c plurium minarum rivulo- rum falfam aquam vehentium, ftatim ex mag- no proventu Salicorniae, Salfolae &..Ana- bafeos dignofcitur. - ' d Terra Jelenitica, in torrente qui urbem Sara- toviam t ran fit in argilla rhomboidali , lamellofa. , nigricante reperitur. . Arena. a Glarea tnobilis ad littora Volgae orientalia pr-ae- fertim reperitur. / 3 Glarea argillofa , hinc inde in pratis, •; traps Volgam. y Sabulum particulis minoribus , fpathi, quarzi, 5c micae compofitum. In medio vafli defer ti trans Volgam, campus ingens hac arena coopertus in longum 140 in latum 50 mil- liaribus patens, & Ryn appellatus, a Volga 100, Yaiko 60 circiter, a mari Cafpio autem. 1 20 milliaribus Anglicis abeft. sifotTfim ; 1 ] ? in nfin'iD (B.) LAPIDES, in univerfum admodumrari. cc ^ uarzofi , in fummis jugis montium cis Vol- gam reperiuntur integrae rupes ex hoc lapide compoiitae, Magnae fatis molis 6c nomine aurium {JJJhyJ appellatae, prope Dmibrefok urbem, trans Volgam, ultra 30 mill. Angl. confpicuae funt. /3 Cofurenarius in fummis montium jugis ibi- dem. . - . ’ Cal car ius , - £.318 1 y Calcarius , petrefa&is teftaceis plenus, in prae- rupta Volgae ripa prope Saratoviam, in ftrato duorum circiter pedum, a fummo montisjugo i o circiter pedibus. $ Lapis margaceus. Omnia Volgae littora om- nel’que citeriores partes nil nift ftrata hujus lapidis margacei habent, qui nec calci fa- ciendae bonus, nec in aedificiorum ufum cedit, quia aeri expofttus brevi difTolvitur. s Tophus fale plenus> in littore lacus Yelto- nienfis. No fa. Trans Volgam ne parvae quidem molis lapides, exceptis his tophaceis, reperies. (C.) INFLAMMABILIA. 1 Gagates 120 milliaribus Anglicis ad Volgae ripam fupra Saratoviam repertus. 2 Pyrites fulpbureus purus nudus 26 mill. Angh fupra Saratoviam in auftrali ripa Tc hardy mi fluminis 6 mill. Angl. a Volga reperitur ; & totus mons ex hoc pyrite verfus Africum (S. W.J ad Kurdyum flumen ufque protenditur. Decern librarum pondo, dant per deftillationem 16 libras fulphuris refiduum vitriolo martis, Scpartibus martialibus eft impraegnatum. (D.) S A L I A. 1 Sal commune. Ingentem falis copiam maximae Rufiici imperii parti fuflicientem praebet lacus Yclton a Rufiis, a Khalmuccis autem Gelton-noor> appellatus. Is 3 t 3*9 ] Is lacus trans Volgam a Saratovia 160, a Dmitrefok urbe circiter 80 Angl. mill, abeft. A campo arenofo Ryn fupra memorato 20 circiter mille pafiibus remotus j 1 o in latum & fedecim in longum, circuitu vero mill. Angl. patet. Plures in eum incidunt rivi falfi. Aqua vix ultra 4 pedes Anglicos fuperfufa, intenfe lalfa, coloris rubicundi, ab argilla ex monti- bus ut credo defluente, forte & ab alia caufa, quam ignorare me fateor: relatum mihi enim eft, lacum menfe Augufto, poft intenfiffimQS calores, maxime rubere. Tertia circiter parte mill. Angl. a littore incipiunt ftrata falis per omnem lacum extenfa, 3 circiter pollices crafia j haec ftrata in medio lacu ad infignem altitudinem reperiuntur. Anno 1746, quum primum hoc fale uti inciperent, curribus per lacum uti per glaciem commeabant, falem ve&uri: fed curiofius inquirentes, quotnam ftrata falis in lacu effent, tandem aquae fub ftratis inclufae locum dedere prorumpendi, -Sc ex eo tempore aqua lacui fuperfufa eft. Mille vel 1200 homines lintribus circiter 400 vel 500 a fine Maii menfis, in altum Angl. cir- citer milliare a littore evedti in aquam defcen- dunt & ope ferri conto impadti, ftrati falis partem aliquam a reliquo revellunt, trium quatuorve pedum plerumque magnitudine, & in lintrem tollunt, dein lintre onerato unus in littus cum fale abit, reliqui alium lintrem replere conantur. Poftero die antequam ad laborem redeant, falem in littore malleis lignei^ comminuunt, & aqua lacuftri eluunt, eft . [ 320 } eft enirn maximopere impurum. Quotennis ad 120 millena millia librarum falis a Maio ad Auguftum eruunt, & 6000 vel 8000 bobus Saratoviam 6c Demetriopolim (Dmitrefok) ad Vrolgamin Imperatricis devehunt horrea, prae- terea innumeri equi, carris jundti, falem in ufum populi in vicinia exportant. Pro 40 libris falis, pm labore, operariis, &iisqui fa- lem vehunt in univerfum Saratoviae 4 L.d. Demetriopoli (Dmitrefok) tantum 2 ±.d. mo- netae Anglicae ex publico rependunt. *Deinde autem falem per omne imperium Rufficum navibus diftribuunt 6c carris. Turn vero omnes unam libram Jj. Angl. pretio, emere polTunt, ex publicis horreis, quovis in loco. Ingens copia falis mirabilis , inter ftrata falis paftim reperitur, 6c licet maximam eius par- tem fupradi&o modo eluant, remanet fem- per aliqua ejus pars, quae efficit, ut hoc fale minus bene in afpergendis utantur carnibus, praefertim in ufum nauticum, ideo in impera- toriae clafiis ufum quotannis Hifpanum im- portant falem. Praeter hunc lacum lunir 6c plures alii fale pleni, verfus mare Cafpium, in vicinia Aftracani j fed eo fale uti vetitum eft, ne in detrmientum publicorum redituum eum eruerent ; id vero inde incommodum ortum, ut pifcatui nunc minus fmt intenti populi Cafpio mari vicini, falis ntmpe pretio duple majpri, quam antefuerat, fado. 2 Sal mhabik uti fupra memoravimus inter ftrata falis communis reperitur, in eodem lacu Yeltonicnfi, 2 T. Ahanen . [ 321 ] Alumen . Urbem Saratoviam tranfit rivulus in praerupta valle, in eundem a parte feptentrionali influunt fontes tres, quorum aqua faporis eft maximopere adftringentis ; cum ea quaedam experimenta inftitui, ut nempe potui; non enim in hifce oris in promptu funt omnia ad ejufmodi expe- rimenta rite inftituenda. a. Odorem nullum in hac aqua obfervare potui. (3 Vifui aqua fe offert limpidiffima ; nec per complures dies aftervata mutationem ullam fubiit. y Sapor intenfe ftypticus, adftringens, amaru- lentus. 3 Media deflate, frigidiffima erat dum ex fonte prod i ret. s Solutio argenti in XT’, aqua diluta, & huic aquae aftufa, eandem fubito turbidam, mox ladtei prorfus fecit coloris : mox coagulatae in aqua videri poterant partes, quae fenfim fubfidere videbantur ; fuperior pars hujus co- aguli nigricantis erat coloris. i C 326 ] 18. Rubia peregrina foliis quaternis; baccac duae monofpermae, femina umbllicata ; fierce m. Jan, ad ripam Dobryn, Kae Sc Yerooflani. 19. Plantago major , ad vias Sc femitas paflim, fh m. Jul. 20. media, in montibus foli expofitis, fl. eodem tempore. 21. Sanguisorba officinalis , copiofe in pratis, fl, m. Jun. feqq. 22. Alchemilla vulgaris in pafeuis humidis, Tetrandria Digynia. 23. Anonymos calyx exterior triphyllus, interior qua driphyllus. Corolla nulla, ffcyli duo plumofl, an- therae majores fagittatae, foliola linearia fafciculata, flores alares, radix lignofa ut Sc tota planta, quae raro pedem Sc dimiduum excedit. Ob feminis defedtum determinare non potui, quo potiflimum lit refe- renda haec planta ; floret Julio Sc Aug. locis aridis in deferto trans Volgam prope Yerooflanum flu- men. Pentandria Monogynia. 24. Myosotis fcorpioides locis humidis floret m. Junio. 25. apula fob Wpidis, racemis foliofis locis aridis m. Jul. 26. Lithospermum offiicinale floret Maio in mon- tibus Sc locis apricis circa Koordyoom Sc Sarato- vian?. ' 3. 3 1 27. Onosma, 0 J C 327 ] 27. Onosma, fimplicijjima fol. lanceolato — linear!- bus, confertiffimis, afperis, antheris fagittatis, quae mihi connatae videbanturj fl. m. Jun. loci's aitiori- bus ficcis. 28. Echium Italicum flor. m. Junio in collibus. 29. Lysimachia vulgaris floret m. Junio locis hu- midis. 30. - - nummiilaria floret m. Auguflo in pratis. 31. Convolvulus arvenfis fl. m. Jul. inter fegetes paffim. 32. • fepiurn inter fentes & dumeta fl. Julio. 33. Polemonium coeruleum in fyl vis & pratis floret m. Maio. 34. Campanula rapunculoides habitat in montofis regionibus fl. m. Junio. 33. aridis & paffim ial- 61. tatarica J fugine alperfis. 62. Lintjm perenni floret m. Jun. & Jul. in pratis prope Coloniam Palatinara. Hexandria Monogynia. 63. Allium paniculatum , floret m. Jun. in locis defertis. 64. Fritillaria Meleagris , flor. April. in montibus aridis ad Volgam. 65. Tulipa JylveJlris , flor. m. April. 66. — Gefneriana locis aridis pul- cherrimis coloribus nonnulla exemplaria fuperbire vidi, praefertim ad tumulos quofdam fepulchrales in medio deferto 60 circiter mill. Angl. ab omni habitatione remoto. 67. Asparagu s officinalis , in omnibuspratisadVolgae ripam copiofe A. m. Jun. 68. Con vall aria maialis flor. in fylvis m. Main; 69. multiflora. jo. bifolia , d. m. Maio in bumidis. 7 1. Acorus Calamus , in aquofis & paludibus paflina. 72. Rumex Acetofat in pratis Jun. Hexandria Trigynia. 73. A l ism a Plant ago aquatica in paludibus ad Haflam & trans Volgam, in. pratis m. Jul. Vol. LVII. U u Hep- [ 33° ] Heptandria Monogynia. 74. Trientalis europaea , fl. m. Maio in fylvis, Octandria Monogynia. 75. Epilobium angufiifol. florent m Tunio lo. 76. birfutum, f ds humidis. 7 7 . tetragonum , J 78. Vaccin ium Myrtillus in fylvis humidis m. Maio fl. 79. — ■ Oxycoccos in paludibus frequens j & modo non omni tempore venum, afportantur baccae Oxycocci, praefertim m. Jun. Rufft eas magna copia ingurgitant, contra calores ; vel etiam fuccum exprefl'um, aqua & melle admixtum, pro potu habent, quern palato admodum jucundum efle, ipfe expertus fum. Octandria Trigynia. 80. Polygonum Biflorta fl. m. Maio in pratis. 81. Convolvulus inter fegetes paflim. Enneandria Hexagynia. 82. Butomus umbellatus in paluflribus m. Jun. Decandria Monogynia. 83. Arbutus Uva urfa propc Twer in paludibus jam in vicinia Volgae fl. m. Maio. 84. Fyroi.a C 431 ] 84, Pyrola rotimdifolia , "1 florent m. Maio in 85. — minor , J fylvis. Decandria Digynia. 16. Sclerantiius annum fl. m. Maiolocis arenofis, radicibus hujus ut & Potentillae reptantis & Tor- mentillae adhaeret coccus Polonicm j & a mulieribus frequenter colligitur, aceto necatur, & venum af- portatur. Decandria Trigynia. 87. Saponaria officinalis , fl. m. Jun. locis ficcis. 88. Di an thus arenarius , fl. m. jul. & Aug. ad: ripas Volgae. 89. Cucubalus tataricus, ~)fl. m. Jun. locis aridis 90. Jibiricus , j & altioribus. 91. Aren aria faxtalis , fl. m. Jun. in montibus flccis ex lapide margaceo conftantibus. Decandria Pentagynia. 92. Sedum acre floret m. Aug. locis arenofis. 93. Telephium locis aridis in deferto. 94. Agrostemma Githago inter fegetes. 95. Lychnis. Chalcedonica prope Coloniam Palati- nam copiofe in fylvis & locis hu midis. Dodecandria Monogynia. 96. Portulaca oleracea ad ripam Yeroofhni fiuvii. 97. Ly« U u 2 [ 332 ] 97* Ly thrum Salt car i a ad rivulos fl. m. Jul. Aug* Fp. * ’ : . fj (hr .1 l f ii on Dodecandria Trigynia. 98. Euphorbia Pep/us fl. m. Julio in agris. 99. ■ heliofcopia ibid. eod. 100. palujlris coloflea 4 & 5 pedum Angl. ad ripas Volgae & Occae in pratis humidis fl. m. Maio. ICOSANDRIA MONOGYNIA. 101. Amygdalus j in campis defertis integrae fylvulae occurrunt, fl. m. Maio. 102. Prunus Ccrafus caproniana in defertis cis Vol- gam, integrae ex ea fylvae reperiuntur, fl. m. Maio. 103. Acacia Germanor . fl. m. Maio inter dumeta. Icosandria Trigynia. 104. Sorbus aucuparia in fylvis m. Maio. Icosandria Pentagynia. 105. Py Rus Mains fylveflris ; in fylvis hinc inde ar- bores majores reperiuntur, fl. m. Maio. 106. Spiraea Jahcifolia herbacea, ad montium ra- dices, floret m. Jun. 107. Filipcndula in campis humidis. io 8. Ulmaria in pratis. 109 Spiraea C 333 3 109. Spiraea crenata J\ tatarica folia ovato ob- longa, alia apice crenata, alia integerrima, coiym- bus terminalis j flores albi ; fl. m. Maio in campis defertis paffim. IcOSANDRIA PoLYGINIA. no. Rxjb us Idaeus magna ingentique copiain fylvis provenit, 6c in montibus fylvofis. in. friiticofus. 3 1 2 . F r a gar 1 a Vejca fy he fir is 6c pratenjis m . Maio. 1 13. P otentili a Anferina in pratis. 1 14. reptans in campis paffim argillolis foli expofitis, coccum Polonicum alit. 1 1 5. Tormentilla ereSta in prato fylveftri m. Maio floret, cocci Polonici ferax. 116. Comar u m palujlre in locis humidis* Polyandria Monogynia. 1 17. Chelidonium majus ad fepes m. Maio. 1 18. Papaver Rhoeas inter legetes m. Junio. 119. Nymphaea ^ ] in flum. Ylafla 6c in pa- 120. lutea > ludibus copiofe trans Volgam. 12 1. Tilia europaea copiofe in fylvis floret. Polyandria Trigynia. 122. Delphinium Confolida fl. a m. Jun. inter fe- getcs. 12?. datum inter fruticeta m. Jul. 124. Aco- [ 33+ 3 124- Aconitum mdnatum , fol. magnis, palmatis, lacinis magnis, flores pallide coerulei fingulares in Querceto humido prope Arfmaflium urbcm, exitu in. Maii. J25. Anemone fylvejlris fl. m. Maio & Junio in humidis & fylveftribus locis. humid. 128. Trollius europaeus fl. m. Maio in pratis. 129. Caltha paluftris ad ripas rivulorum in April. 130. Aiuga pyramidalis fl. m. Maio in campis. 13 1. Siderit i s hyffopifolia fl. m. Jun. in campis de- fert. cis Volgam. 132. Mentha aquatica fl. m. Jul. paluftribus. 133. Glecoma hederacea in pratis copiofe fl. m. Maio feqq. 134. Galeopsis Ladanum fl. m. Jun. in arvis. 135 Phlomis Ilerba Venti fl. m. Jun. in campis. 336. Origanum vulgar e fl. m. Jun. inter fruticeta. 137. Thymus Serpillum fl. m. Jun. locis flccis mon- tofis. 138. Dracocephalum fibiricum fl. m. Jul. J 39- Scutellaria galcriculata fl. m. Jul. locis humidis. Polyandria Polygynia. 126. Thalictrum flavum minus Didynamia Gymnosperma. 3 Djdy- [ 335 ] Didynamia Angiosperma. 140. Rhinanthus corollis labio fuperiori, recui-vo emarginato j flores pallide lutei, alares in fpica homo- malla, fol. lanceolatis integerrimis, fl. m. Maio & Jun. in campis & fylvis arenofis fubhumidis. 141. crifla Galli fl. in pratis m. Jun. 142. Euphrasia officinalis , 1 In campis defertis fl* 143. — — Odontites , J in Maio & Junto* 144. Melampyrum arvenfe inter fegetes Jul. 345. Pedicularis comofa , flore pallide luteo, m. Junto in campis. 346. Antirrhinum Linaria fl. m. Jun. in campis. 147. Scrophularia nodofa fl. m. Jul. ad. aqua- rum rivulos. 148. Orabanche major fl. m. Jun. in montibus. 349. Dodartia orient alis, fol. integerrimis gla- bris linearibus, flor. caeruleis; fl. m. Julio in campis trans Volgam ad Tarlyk majorem fluvium. Cameli, equi, boves & oves Khalmyccorum funt ejus appetentiflimae, & ad radices ufque demorfam comedunt j ideo magno labore & longiflima excurflone demum locum intadtum nadtus lum, in quo exemplaria integra reperi ex quibus earn definire potui. Tetradynamia Siliculosa. 1^0. Alyssum incanum in campis fl. m. Jun. Tetra- [ 336 ] Tetradynamia Siliquosa. 151. Sisymbrium Sophia fl. m. Jun. in aridis. Monadelphia Polyandria. 152. Sid a ; calyx tomentofus, coriaceus, quinqueir- dus, complicatas, folia magna, cordata, crenata, acuminata, tomentofa, petiolis folio longioribus j capfulae tomentofae, 12, 13, 14, calyce longiores, femina in qualibet capfula tria, reniforma, d. m. Aug. ad Yerooflani ripam. 1 53- Althaea officinalis dor. m. Jun. in campis humidis. 154. Lavatera thuringiaca d. m. Jun. inter fruticeta. Diadeiphia Octandria. 355* Pol /gala vulgaris j d. m. Jun. in carrrpis 136. fibirica J herbods. Diadelphia Decandria. 1 $7- Spartium complication d. m. IVTaio locis ficeis. 1 58. Gen ist A tinEloria fl. m. Jun. & Jul. in campis iierbidis patentidnms. 149. Lathyrus tuber of us, ~j d. m. Junio copiofo in 160. • -- ■ pratenfis , j pratis & campis.. 16 r. Vi ci a piriformis y dylus villofus petiolis angu- Jods lubdriatis, dipulis dnuato-fagittatis, foliis ova- tis, retufis, mucronatis, pedunc. multidoris imbri- cate* t 337 . catis, flores cchroleuci ; crefcit inter dumeta in ripa rivuli in Colonia Palatina. -362. dumetorum, inter fruticeta, j m jan 163. Cracca in pratis, J 164. Glycyrrhiza echinata fl. m. Jun. ad ripatn Volgae & Dobrinkae in pratis. 26^. glabra , integros ubiqueac fpa- tiofiflimos campos occupat, fl. m. Jan. 166. Coronilla varia fl. m. Jun. in campis & pratis. 167. Hedysarum Onobrychis fl, m. Jun. in mon~ tibus margaceis. 368. Phaca alpina fl. m. Jun. in campis. 169. Astragalus contortuplicatus m. Jun. in campis ficcis* . . _. jy0> — pilofus in aridis locis fl. m. Julio. jij] . __ Syriacus, in locis altioribus. 172*. Trifolium Melilotus officinalis, toti campi meliloto, fl. luteo & albo, occupantur. jyg. -rube”' fl. m. Jun. in pratis. POLYADELPHIA DlANDRIA. 174. Hypericum perforatum, inter fruticeta. SYNGENES1A PpLYGAMIA AeQUAL. J7^. Sonchus Alpinus in campis altioribus fl. m. Jun. . . . . . 376. Leontodon Taraxacum in pratis m. Maio. inn. Cichorium Intybus, fl. m. Jul. in campis. 378. Arctium Lappa ft, m. Jun, ad fepes. Vox.. LVII. Xx 179. Eupa- [ 33§ ] 1 79- Eupatorium cannabinum fl. m. Junio ad aquarum rivulos. SVNGENESIA Pol YG A MIA SuPERFLUA. 180. Tanacetum vulgare m. Jul. in campis 5c ad fepes. 1 81. Artemisia Abrotanum ad Volgae 6c Occae ri- pam copioflfiime. 182. — — Pcntica fl. m. Aug. in campis aridis. 183. ■ — Abfynthium in montibus ficcis. 284. vulgaris ad fepes. 185. ' ■■ ■ ■ Dracuncuhis in campis patentibus & ad montium radices. 186. Senecio Donia fl. m. Jun.in pratis. 187. Inula Helenium copiofe in pratis & ad rivulos m. Jun. 188. Cineraria Alpina , 8c quidem ea varietas quam Jaquinus in fl. Vindeb. p. 287. nudam vocat, in montibus margaceis ficcis. 189. Achillea ptarmica in pratis trans Volgam co- piofe m. Jun. 190. Millefolium in campis ad fegetes 6c vias paffim m. Jul. Syngenesia Polygamia segregata. 191. Echinops Sphaerocephalus in campis ficciori- bus. Syngenesia Monogamia. '}> 192. Viola tricolor pnffim in arvis & pratis trans Volgam, *• » » 1 y* I93. IM- C 339 193. Impatiens Noli 4 anger e inter fr.utices hi. Jun. Gvnandria Hexandria. 194. Aristolochia Clemalitis in fvlvofis m. Maio floret, Monoecia Tetrandria. I95* Betula alba fi. m. Apr. fylvar. decus; 196. Aims fl. m. Apr. ad ripas aquarum, 197. Urtica diotca fl. m. Jun, ad fepes. 198. Morus Tatarica habitat in Infulis Volgae, quo- tannis inundationi expofitis circa Tzaritzinum, ubi integrae ejus funt fylvae, lie & in omnibus infulis Tanais aboflio ejus ad Tzaritzinum ufque reperitur copiofe. Bombyces foliis hujus mori educati, feri- cum produxere tanti fplendoris, adeoque bonum, ut nulla in re inferius fit ferico Taurinenfi. Impera- trix ipfa ex ferico a me oblato, juffit fieri pulcher- rimas fafeias, quas capitis ornatus caufa admovere dignata eft. 199. Xanthium Jlrwnarium ad fepes 6c vias pafiim. Monoecia Polyandria. 200. Quercus Robur. Sylvae ad Volgam 6c in- feriora Tanais funt maximam partem quercetum continuum, quod memorandum, quia quercus rarae in feptentrionalibus Rufiiae. Incolaequer- no ligno in aedificando & in foco utuntur : juniores X x 2 quercus • [ 340 ] , quercus pifcatores frequenter caedunt, ut cortice querno, additis veteribus ferramentis, retia nigro tingant colore, magno fylvarum damno: quamob- rem ipfe aliam in Boruflia ufitatam propofui me- thodum retia nigro induendi colore, nempe ut fumigentur, quod & magis conducat retibus, & pifces allicere credatur. Monoecia Monadelphia. 201. Pinus fylvejlris, hujusarborisfolas quinque vidi ad villam Sofnofkam, quae hinc & nomen fortita eft : praeterea defunt in ripis Volgaeper plusquam 600 mill, Angl. a mari Cafpio. Dioecia Pentandria. 202. Humulus Lupulus arbores fcandit inlocis hu*' midis, Dioecia Octandriaj 203. Populus alba 'j integrae fylvae in pratis 204. tremula inundatis,transVolgam> J harum arborum. Polygamia Monoecia. • 4 • * • • - '• 205. Veratrum album. Incolae credunt, id comefum pecoribus omnis generis mortale effe. Radicem ficcatam & in pulverem redudtam, vul- neribus in tergo bourn infpergunt, & hac ratione oeflruin C 341 3 oeftrum expellunt. Copiofe fl. m. Maio in iocis humidis circa Saransk & Penfam urbes. • 206. Acer Tataricum ft. m. Maio ad ripas rivulorum & locis humidis. » • Cryptogamia Filices. 207. Marsilea natans. Folia plantae ovata, op^ pofita, complicata; omnem fuperficiem foliorum te- gunt glomeruli ex quatuor albis filamentisin apice veluti cirrhoideis, compofiti. Infra ramulos plan- tae, multae in aquam radices demittuntur; diverfi hinc inde ab his radicibus reperiuntur glomeruli pi- lorum, quicalicislococinguntglobulos tres, quatuor, quinque, ieptem, plures glomeratim adhaerentes, & ftylis tenuifiimis inftru&os, globuli maturi conti- nent femina plurima albicantia ovata. Itaque nunc credo hac obfervatione me fatisfadfurum defi- derio 111. Linnaei , qui genus Marfileae deter- minare promifit, ft haec Marfileae fpecies examinata. fuerit. Integrae paludes trans Volgam hacce planta funt tedlae. Quae hie deferipft nonnift oculo armato vidi m. Aug, R E G N U M ANIMAEE, Classis prima. Mammalia Terrae. \ 1, Canis familiaris domejticus , inter rufticos fre~ quens. 2. 'vertagus , hie uti in omni Rufila haec ca- - num fpecies pilis Iongifiimis, & pedibus durioribus c; hub* I I L 342 ] fubvillofis, videtur adaptata regioni nivibus hieme opertis, ideoque 6c turn ad venationem adhiberi poffunt, quum. reliqui vertaginil proficiunt. 3* — Lupus , frequenter admodum 6c pecori- bus damnofi funt lupi, hifcein oris. 4. — FulpeSy ex utraque Volgae ripa frequentes; ipfe catulum captum vidi trans ^olgam ad Tarlyk ftumen. .< 5* Felts Cat us, Feles ferae in fylvis frequentes di- cuntur, a me tamen non vifae. 6. Mustela Lutra. In paludibus 6c Iacubus trans Volga m plurimas Lutras effe, relatum mihi eft : vidi unam, mox fe aquae immergentem. 7* MarteSy pelles earum a rufticis frequenter in urbes venum-afferuntur, non tamen magni fa- ciuntur. —————— PutoriuSy 6c harum pelles faepius ve- nales. 8. Ursus ArftoSy ad Galkam rivum prope coloniam, pauloante meum adventum3quinquefimulfunt vifi ; alius hieme Coloniam Palatinam placide tranfiit, & intadus fylvam vicinam attigit. Bestiae. 10. Sus Scrofa 3 a Rufticis heic fatis magnae aluntur fues. Apri circa Aftrachanum in arundinetis, prope Cafpium mare admodum frequentes obvii. 11. Erinaceus EuropacuSy in fylvis 6c montibus re- periuntur. 12. Talpa lEiiropaeciy reperitur quidem, fed ra- ro. ...rq i'.ijV ^ * '* ’ ' \ , - ' l XX f I It . . ^ ' • Glires [ 343 ] ;v . ft in'" • 1 • ' . •rtnih-' ft- ' '-I ' .* - Glires. 13. Lepus ftmidus. Heic loci duae fpecies lepo- rum repcriuntur. Una hieme alba, exceptis auri- bus, aeftate rufam grifeamque lanam rurfus in- duit j at haec fpecies minor eft, eorumque lana a pileariis ufurpari nequit. filter a fpecies omni tempore aeque rufjo-grifea, fed major, 6c lana earum a pileariis ufurpatur. Ex fola Vorainia, quotannis hujus fpeciei ultra 60,000 pellium Mof- cuam 6c Petropolim dein devehuntur, unde poftea navibus ad exteras oras praefertim in Angliam exportantur. 34. Mus Marmotta , in campis defertis inter Penfam Petroffk 6c Sarotof urbes ingens Marmottarum copia eft; cauda pilofa admodum. 1 S' — - — cauda fubabbreviata, auriculis fubrc- tundis, pedibus brevioribus, palmis fubtetradac- tylis, plantis pentadadylis, ventre adipofo terrae adpreffo, corpore fubtus pallide luteo, in dorfo grifeo lutefcente, magnitudine exceditRattum. 16. Rattus , 1 in horreis 6c domibus jy. Muf cuius , J habitant, Pecora. 1 8v Camelus Raft ri anus, topbis dorfi duobus. Una varietas colore fufco, altera pallide fufco-aibicante ^ haec rarior. Khalmycci eis utuntur, 6c pretium eis 12 vel 16 aureor. (Guinea vulgo) conftimunr. Khalmycci 6c Nogaiji Tartari prope Aftrachanum ex lana camelorum ncta 6c texta pannos egregios cm- / [ 344 ]_ conficiunt, noftro Camelot fimillimos, quos ipfe vidi ; fic 6c funes optimos ex his lanis torquent. .19. Carr a Hircus. Tres ejus hie funt obviae varietates. 1. Capra vulgaris, per totam Ruffiam eadem. 2. Capra Khalmyccica> non nifi pedibusbreviori- bus diftinda, ut 6c totum corpus praecedente multo minus. 3. Capra Angorenjis in Orenburgenfi praefedura apud Vrirgifos paffim obvia ; fic 6c curiofitatis gratia Aftrachani, ex Ghilano Perfiae pro- vincia, ad vedas haberi capras hujus fpeciei, ex teftibus fide digniffimis audivi. Lanas ex Perfia advedas 6c a colonis Germanis, in fi- lum netas 6c textrinae adhibitas, vidi cum ferica. 20. Sayga vulgo Ruffis, relatum mihi earn in campis defertis patentibus frequentem effe ; ipfe non vidi, his locis ; cornua vidi 6 uncias Gallicas paullulum excedentia, teretia annulata, reda in apice paullulum incurvata. Dein Petropoli, ani- mal vidi, circiter duos pedes Parifinos, 6c quod excedit altum, coloris pallide admodum rufefeen- tis, fubtus albicantis. a 1. Ovis. Aries. Tres heic funt varietates ovium. .a Rufjica vulgaris quarum lana, pilis caninis propinquior, non magni pretii j 6c quod ruftici millam earum curam habent indies lana de- terior fit j minores. b Khalmyccicae oves , funt Rufficis multo ma- jores, capita 6c nares incurvae, aures pendulae, pedes elongati, cauda lata, crafla, adipola, ultra [ 345 1 ultra 30 libras pendens, lana in adultioribus pilofa rigida, in agnisundulofa fplendens; a magnatibus Rufliae in vefles hibernas expe- tuntur pelles agnorum, 6c magno latis pretio emuntur. Khalmycci pelles has perficiunt ladle, unde id commodi habent, ut non folum tint molliffimae, verum 6c madefadtae 6c de- nuo liccatae non rigidae bant. Oves ufque ad 200 libras funt ponderofae. c Tcbercajjicae oves lanam Anglicaeprorfusaequa- lem geftant. Hae oves circa Medvedizzam flumen hafceri poftunt. Quum Imperator Pe- trus anno 1722 arma in Perfiam expediret, 6c Tchercallicas videret oves, edidlo propolito juffit ut per omne Adracaniae 6c Cafaniae regnum halce oves folas alerent, unde quae- dam hue pervenere ; mortuo autem paucis poft annis Imperatore edidtum hocce prorius neg- ledtum : praeterea ad fluvium Ivynel colonia eft TchercafTorum, in Orenburgenfi prae- fedtura, quae has oves fecum adduxit. 22. Bos Taurus. Boves Ruftorum funt minores, Khalmyccorum majores, maximae ex Vorainia ad- dudtae. 23. Equus. Caballus. a Ruffici equi funt minores, dun 6c longinquis itineribus apprimis utiles. b KbalmycciciEqui, paullo majores Rufticis, duri, im- primis in longinquis itineribus utiles, gramenquod- libet, etft durum, ftramineum, frutices imo aequi bonique faciunt; triduo ad 400 milliaria Anglica curfu perficiunt. Venditi aKhalmyccis non raro per plufquam 100 Angl. milliarium fpa- Vol. LVII. Y y tium [ 34-6 ] tium per defertaad fuos redeunt dominos, faepe & Volgam tranant. Hieme fub nive pede ci- bum quaerunt. Nagayenfes 6c T’urcommannici 6c Bajhkirici ma- xime vero Kirgifici Equi multo his funt vali- diores 6c majores, laboris feraeiflimi, aeque af- fueti ungula lub nive paftum quaerere. d T chercajjici Equi, Khalmyccicis vix majores, nec forma praeftantes* nam cervix eis rigida, & cum plurimis equis ea fit convexa, his ut pluri- mum eft concava, at curfu longe omnium velo- ciftimi, 6c aeque ut reliqui laboris feraeiflimi* triduo ultra 500 imo 600 mill. Angl. perficiunt. Caro equina Khalmyccisprocibo, pullusinter lautiora reponitur, lac pro potu, acefcens, fermentans 6c deftillatum inebrians, Kumys j bis deftillatum Arecca appellatur, faporis admodum ingrati. CLASSIS SECUNDA. AVES. Accipitres. 1 . F alco, Melanaetes, Aquila , V aleria , cera pedibuf- que luteis. Ipfc pullum hujus generis, plufquam duos pedes Anglicos longum vidi, circa Dobryn- kam. 2, aerugbiofus, cera luteo-viridi, corpore grifeo fufco, pedibus luteis, ubique palfim ciica Volgam obvius. Co/fi; • 1 y n ill U41-. / (i 1. * j 0 EC ..J . Ficae. Cn'-'i C 347 3 Pi cae* . Corvus Corax. . , . - .. Cor nix. . . Frugilegus. . ■ — Monedula . . . Monedula lota nigra , nec unquam caeru- lefcens, occipite incano, fronte, alis caudaque nigrisj magnitudine monedulae vel parum minor. Omnes hi Corvi in fylvis ad Volgam frequentes. 8. , ■ ■■ glandarius, Pica Glandaria. 9. Pica. Pica varia. 10. Gracula Atthiiy corpore viridi, dorfo cae- rulefcente, abdomine ferrugineo, pedibus rubris, magnitudine monedulae ; trans Volgam ad Yeroo- flanum flumenvidi. 11. Cuculus canorus in fylvis paftim auditur. 12. Picus martins ”1 circa arbores putrefcentes fre- 13. medius I quens uterque. 14. Merops Apiafler gregatim trans Volgam ad Yerooflanum flumen vidlitat. 1 5. Up up a Epops ad ripas rivulorum in fruticetis prope coloniam Palatinam a me vifa. Anseres. 16. Anas CygnUs in lacubus ad Volgam frequens; j j' Cygnoides orient alis f. Anfer Mofcoviticus roftro luteo cera magna nigra, occipite atro, facco o-ulari; corpus grifeo-luridum, albo mixtum, pedes luteo-rubicundi. Paftim ut Anfer domefti- cus alitur ; tamen multo major eft. jS. Anfer. Anferes feri innumeri in paludibus Y y 2 trans [ 3+8 ] trans Volgam degunt. Anfer domefticus ubique alitur. ig, . Anas mofchata fera & domeftica, his locis habetur. 20. Bojchas major 21. clypeata 2«. ... — platyrhynchos 23 24 •rr Hae fpecies roftris dilatatis in lacuftribus circa Voi- gam funt frequentes. Penelope f. anas fufca , capite rufo, fronte alba, cauda acuta in lacuftribus circa Volgam. - Jlrepera 25. An as Querquedula 26. - — » Crecca Harum fpecierum innumeri greges in paludofis trans Volgam habitant. 27. Pelecanus Onocrotatus , corpore albo lutef- cente in dor fo coloris pallidefufci. Roftrum ultra pedem Anglicum longum, inferior mandibula bi- furca, cum facco gulari, in ripa Yeroofslani 18 vidi. 2g. _ Car bo cauda aequali, corpore ni- gro, roftro edentulo, in apice incurvato, pedibus nigris tetradadfylis palmatis in occipite cranium in proceftum pfleum acutum finitur. ig. Col ym bus auritus in Volga & lacubus vlcinis obvius. Grauae, o0. Platalea Leucorodia coloris albi, pedibus roftroaue, apice rotundato, dilatato, rubris, ad Vol- gam frequens. 3 1 . Ardea Grus ad Volgam. o 2 . - — — Cinerea major ibidem. 43 • ■ 35 tore grifeo. [ 349 ] 33 . . — > Jbis nigra> roftro arcuato, pedibus Sc roftro luteo-rubicundis, corpore nigro, viridefcente, magnitudine corvi cornicis, at elatior ob pedes collumqueelongatum,longitudo ultra 3 pedes Angl. a roftro ad pedesj gregatim in paludofis Volgae de- git, ibique ranis, lacertis Sc ferpentibus viditat. 34. Scolopax rujiicola in fylvofis ad Volgam, the Wood- cock . Phaeopus colore fufco rufefcente, pec- The Wimbrel. Gallinago. The Snipe or Sniie. minima. Priori ftmilis, fed multo minor, plumulis crinibus fimilibus. The Jack- Snipe. 38. Tjunga Vanellus, "| ad Vol admodum 39- Glareola, ^ frequentes aves. 40. * HypoleucuSy J 1 41. Charadrius Oedicnemus in campis defertis trans Volgam. 42. Fulica atra , fronte calva coccinea, corpore nigro viridefcente, pedibus lobatis viridibus ; in paludofis hiemat fub aqua ut hirundines* quod ipfe in Boruffia expertus fum. 43. Rallus Crex in humidis ad Volgam. 44. Otis Tarda habitat inter fata. 43. Tetrax in campis defertis trans Volgam obvia. 36- 37- Gallinae. 46. Pavo criftatus a magnatibus alitur, Sc ova parit quae a gallinis Sc meleagridibus excluduntur. 47. Meleagris [ 35° ] . 4/. Meleagris Galhpavtis domefticus Ubique alicur. 48. PhasianuS Gallas, Copiofe alitur haec fpecies. 49. Tetrao Tefrhc in betuletis cis Volgam. 50. _ Lagopus hieme albus, exceptis redtrici- bus, 6c aliquot pedtoris maculis rufis. £i. Coturnix copiofa, in fatis ex utraque parte Volgae. Passeres. ^2, Columba oenas domejlica, in villis alitur. Palumbus in fylvis frequens. 54, T urtur major domeftica, colore grifeo-inearnato, macula laterali colli nigra, in fylvis cis Volgam frequens. 55. Alauda arvenfis in utraque Volgae parte, in campis admodum frequens. ;6. Veltonienjis roftro cylindrico, fubulato, redlo ; lingua bifida. Unguis pofticus redlior; digito multo longior. Rojirum ad bafin nigrum, craffiufculum, apice albefcens. Corpore alifque nigris, in capite, dorfo, 6c in fummis alis, pennis paucis rufefcentibus, fexta remigum margine ex- teriorealbaj duae mediae redtrices rufae. Grega- tim trans Volgam in vicinia lacus Yeltonienfis de- gunt hae Alaudae. Alaudae Teltonienfes appellan- tur. Saporis exquifiti, 6c admodum funt pingues menfe Augufto, magnitudine Sturni. Sturnus vulgaris. In pratis trans Volgam in- numeri fturnorum greges vidlitant. 58. Turdus muficus in fylvis ad Volgam. qo. Loxia pyrrhuta in fylvis ad Volgam. 60. Em- 5 Carduelis , 1 . , . > in campis obviae. ms , J r [ 35r ] 60. Embkriza cahndra "1 . . r z . . „ f in campis frequens. 61. citrinella J 1 -1 62. Fringilla coelebs in fylvis, 63' " / 64. Linarius , 65. — Schoeniclus in arundinetis ad Ylav- lam & transVolgam. 66. domejiica ubique frequens. 67. Motacilla Lufcinia j fylvas cantu replent innumerae. 68. Curruca in fruticetis ad Volgam. 69. flava in campis reperitur. 70. ■■ —> ■ --- alba , pedtore nigro, ad aquas fre- quens. 71. Parus major in fylvis. 72. ■ ■ ■■ ... palujlris in falidkis 6c arundinetis props Volgam. 73. Hir undo urbica, fub tedtis nidulatur. 74. . riparia , in defer to ad flumina Yeroo- flan, Targun, Cuba, etc. in foraminibus vidti- tat adeo frequens, ut multa millia fimul video, pofiint. C L A S.S I S X E R T I A. AMPHIBIA, • J i i .mu JReptili a. j. Testud.o lut/iria ; .minorem ovo exclufam at mortuam reperi, trans Volgam; innumerae'hujus .generis in kjcubusad Volgam- habitare drcuntur, 2. La cert A Yigilis in campis aeftu torrentiSus nbi- que obvia,. grifea maculis nigris. ‘ 3. Ran a [ 352 ] 3. Ran A temporaridy 4. — efiulenta , ' ingens ranarum copia in pa- ludibusadVolgam;&quod obfervandum, jam hie cla- moribus fuis, aerem re- plent, cum in reliqua fep- tcntrionali RuftH Tint mutae. Serpentes. ' * / q. Coluber magnus ad 2 & 5 pedes Angl. coloiis grifei caerulefcentis, maculis nigris, Tub abdomine iutefeens, venenofus efte dicebatur j nonnifi par- tem exuviarum vidi. 6. colons lividi, caput triquetrum, cor- pore latiore macula coloris rubicundi in capite, ab- domen crallius ; venenatus, in terra & aqua vivit, fibilat; ad Volgam & Yerooflanum invenitur : ad 3 pedes longus. t n. Coluber coloris grifeo-fufei, fafeia nigra teilel- Jata in dorfo, fefquipedem longus, in paludofts vi- vit. Nantes. Acipenser. Spiracula lateralia folitaria, linearia. Os Tub capite retradtile edentulum. Cirri Tub roftro ante os, in omnibus quos vidi,quatuor, Cauda furfum recurva. . . 8. Sturio roftro brevi obtufo redto, cirrhi quatuor ante os. Caput compreflunij icripta. ofta figuris afterifeorum in- Corpm 6 [ 353 ] Corpus quinquangulare, pyramidatum, dorfo fafti- giato. Cutis fcabra cinereo-flavefcens. Caro rubefcens. Squamarum ofTearum feries quinque. Series i. Dorfalis fquamis majoribus retrorfum uncinatis 14. — 2 & 3 Late rales 37. 4 et 5 Abdominales inter pinnas pe&orales 6c ventrales 1 1. Longitudo 6 ad 16 pedes Angl. 7. Shyp ; rojlro elongato, acuminato, rec- to. Cirri 4 ante os, carne minus fapido, a me non vifus. 10. 1 ■ — — ■ Ruthenus major rojlro elongato acu- minato, veluti vagina tedo, paullulum fupino. Cirri 4 ante os. Caput compreflum, offa figuris afterifcorum infcripta. Corpus quinquangulare, py- ramidatum, dorfo faftigiato. Cutis fcabra flavefcens, Caro rubra. Squamarum aflearum feries 5. Mag- nitudo a 4 ad 10 pedes. 11. ■— Ruthenus minor , rojlro elongato acu- minato redo. Cirri 4 ante os. Caput compref- fum 5. Corpus quinquangulare. Cutis fcabriufcula, atrocinerea. Caro rubra. Squamarum ofTearum feries 5. Magnitudo ad 4 pedes. 12. 1 Ruthenus minor , rojlro brevi obtufo, redo. Cirri 4 ante os. Caput compreffum, offa figuris afterifmorum infcripta. Corpus quinquangulare, pyramidatum, dorfo faftigiato. Cutis fcabriufcula, colore atro-cinereo, in abdomine flavefcens, circa caudam teflellata. Caro alba. Squamarum or- dines 5 ofTearum, uncis parvis inftrudae. Z z Vot. LVII. Series [ 354 ] Series i Dorfalis fquamis majoribus retrorfum uncinatis 12, 13, 14 vel 15. 2 Sc 3 Later ales 69 vel 70. 4 & 5 Abdominales 10 vel 11 inter Ped. Sc Vent, pinnas. Longitudo raro 3 vel 4 pedes excedit. Pinna dorfalis prope caudam ofliculis 46. Pin. Ped, 36. cum prima rigida. Pin. Ventr. 24. Anal. 27. Caud. 150. — Beluga f. Sllbula. Roftro brevi ob- tufo' redo. Cirri 4 ante os. Caput triquetrum. Corpus teres conicum. Cutis laevis,in dorfo nigri- cans, fub abdomine alba, circa caudam teftellata. Caro alba. Squamarum feries 5 depreftae. Longi- tudo a 4 ped. Angl. ad 16. Tres ejus varietates dicuntur, quasnonvidi. Qbfervatio. Omnes hi pifces ex membrana in- teriori (Angl. found dida) dant Ichthyocollam, at Beluga praebet optimam. Sic Sc garum ex omnium acipenferum ovis fieri poteft, ex Rutheno minore optimum. Verno tempore raro hi pifces capiuntur, aeftate pauci, utplurimum tamen Ru- theni minores. Autumno jam frequentiores cap- turaej hieme maximae pifcaturae fub glacie infti- tuuntur. Hi enim pifces in profundiftima loca flu- minum Volgae Sc Yaiki gregatim coeunt, Sc om- nem locum ab imofundofluminis ad glaciem ufque repient. Hibernis copiis acipenferum inventis,die pod Feftum Chrifti nati, omnes accolae fecuribus Sc uncis conto longiflimo impadis, inftrudi ad hunc locum contendunt ; aperta glacie quilibet uncum demittit, Sc ope ejufdem pifces in glaciem extrahit ; ft majoris molis pifcem eft nadus, advocat [ 355 3 advocat vicinos ut opem ferant : jundtis itaque viribus pifcem extrahunt,8cin commune vendunt. Sic quotannis multa millia Acipenferum capi- untur, & excepto Rutheno majore, omnes Cafpii littoribusque vadolis ova deponere videntur ; hujus folius pilciculi minuti duarum unciarum in fluminibus capiuntur, reliqui nunquam 8 unciis minores. C L A S S I S QJJ A k T A. PISCES. Thoracici. 1. Perca Jluviatilis, pinnis dorfalibus diftin&is, fe- cunda radiis fedecim, lineis utrimque fex nigris, pinnis ventralibus ruberrimis. Perch. 2, Lucio-perca , pinnis dorfalibus diftindtis, fecunda radiis 25. Pinna Dorfi I. 14. II. 25. P P. 15. P. V. 6. P. A. 15. C. 22. cauda iinuata. 2# — Lucio-perca minor > pinnis dorfalibus dif- tindtis, fecunda radiis 22. Abdominales* • 4. Esox Lucius Membr. Branchioft. P. D. 22. P. P. 14. P. V. 11. P. A. 18. C. 25. r. Clupea Membr. Branchioft. VIII. P. D. 15. P. P. 14. P. V. 9. P. A. 19. C. 25. Latitudo ad Longitudinem 4. Venter cultra- tus, abdominis carina fpinis acutiffimis praedita, fquamae argenteaej faepe ad duos pedes longus. Z z 2 ■ 6. Cy- [ 356 ] 6. Cyprinus Carqffius , cauda Integra, fquamis aureis nigricantibus, linea laterali reda. P. D. 19. P. P. 1 5. P. V. 9. P. A. 8. C. 24. 7* — Tinea, cauda integra, corpore mucofo fufeo. P. D. 11. P. P. 1 7. P. V. u. P. A. 10. C.25. 8. Cyprinus, an Cephalus ? Dorfo capiteque craflo, pinnis ventrali & anali rubicundis, rquamis magnis; longus 4 ped. ufque ad 2 ped. Parifinos; latus 4 uncias, circa pinnas ventrales, cauda integra. 9* Idas. Cauda bifida. P. D. 11. P. P. 16. P. V. 9. P. A. 12. C. 23. I0- Jeffs pinnae ani & ventrales rubrae pedorales, fufeae, cauda bifida, P. D. 11. P. P. 15. P. V. 9. P. A. 12. C. 22. AJpius ? capite acuto, fquamis magnis, longus 2 ped. Parilin. lat uncias 54. circa pinnas ventrales. P. D. 11. P.P. 18. P. V. 9. P. A. 16. C. 23. 1 2 . — — — Alburnus. P. D. 10. P. P. 16. P. V. 8. P. A. 18. C.22. 13* Brama minor pinnis omnibus nigri- cantibus, nonnifi magnitudine a Brama differt, nec tamen idem, aetate diverfus. P. D. 12. P. P. 15. P. V. 9. P. A. 24. C. 27. 14. Brama major. P. D. 12. P. P. 15. V. 9. A. 27. C. 28. 1 5. cultratuSyVe ntre acuto cultrato, dorfo redo, fquamis argenteis minoribus, longus ufque ad duos pedes Parifinos, lat-. uncias 4 4. P. D. 10. P. P. 17. P. V. 8. P. A. 44. C. 26. 16. Cy- [ 357 1 i6. Cyprinus, an Ballerus ? admodum latus & tenuis, argenteis fquamis. P. D. 1 1. P. P. 16. P. V. 9. P. A. 29-30. C. 25. ’ ■ * ^ ^ A rt r f f •* ■, q «- A • Hie fubfifto; & Specimen Hiftoriae Natural ip Vol- genfis finio, fperans fore ut eo & plures excitenttn* ad his perfe&iora edenda. * f 6 ! ' )\ * • Ji * M v*' •• 1 - * * ' “ Dabam Londini,die xxviii Febr. anni 1767. Joannes Reinholdus Fofjler.. XXXII. [ 358 3 • " ' «-'• - . . . . • *‘*r ■- 1 * * , , . t ? ■ • \ ' - t ~ r i r , w "• ■'*, , f 4 ' . ** 4 . * •• . t i XXXIV. De Problemate quodam Algebraico^ deque evolutione mechanic es cujufdam Cur- ves inter infmitas hypermechanicas , ques determinates cequatio7ii fatisjaciunt . AuSiore Pio Fantoni, Mathematico Bononienfi. Communicated by Sir Horace Mann, His Majeftys Envoy at Florence. / ' « Read June 25>/<"''\UI in computationibus analyticis *767* II verfari folet, animum non modo in ea praefidia folet intendere, quibus problemata dedu- cuntur ad aequationes, fed maximam ubique exoptat concinnitatem, atque elegantiam, ut univerfi operis apparatus, conftrudio, utilitafque commendentur. Quantum vero elaborationis, ac ftudii plerumque ad bffic fingula requiratur, ii probe intelligunt excellen- titfimi viri, qui fe jamdudum algebrae dediderunt. Veruntamen fateri ultro debent, non mediocrem ali- quando utilitatem obtineri poffe ex hujufee potius, quam illius methodi applicatione. Fit enim non raro, ut cum quaeftionem aliquam fubtili licet ingenio verfatus fueris, alia tandem methodus meliori au- fpicio fufeepta, illico tibi elargiatur clariorem ube- rioremque ejufdem quaeftionis folutionem, ex qua multa praeterea obtineas quae admireris. Id vero mihi o in [ 359 ] in fublimi problemate quodam algebraico, an bene feliciterque contigerit, veftro judicio, Academici fapientiftimi, quod maximi facio, decernendum relinquo. Si interea, ut exoro, hanc meam elucu- brationem fumma humanitate veftra excipietis, ea deinceps utar in aliis non contemnendis rebus turn phyftcis, turn mechanicis, ut veftra fapientia duce, facilius ad quafdam nature adhuc reconditas leges pervenire pollim. Nunc porro velim intelligatis, me in hoc argu- mento analytico, de quo loquor, tria maxime pr«e- ftitifte. Primum enim curvam quandam exploravi- mus fuis coordinatis ad axem,& licet ledbifiimis pras- fidiis uft fuerimus-in feparatione indeterminatarum, licet inveftigationem noftram fatis ultro promotam confpexerimus, in aequationem tandem, ut dicunt, hypermechanicam irrumpere opus fait, in earn vi- delicet, quag expofcit mechanicam quadraturam cui- varum exigentium primo mechanicam circuli quadratu- ram. Ex hac autem fere inextricabili conftrudtione non ea certe confedftaria, quag in votis erant, erift elegantiftime potuiffent. Quare difficultate reiveluti commoti, fatis opportune curvam noftram ab axe ad focum deduximus, atque hoc modo univerfum illud opus, cujus dilucide enodandi fpem omnem antea demifimus, eo tandem fehciter perduximus, ut ipfum recte eftet, nobifque plene fatisfaceret. At vero in hac fecunda problematis mei parte dum con- tendo, dum ilia m conftanti animo defugio hy- permechanicam conftrudtionem, atque ad pure me- chanicam propero, invenio tandem. in inunita cur- varum hypcrmcchanicarum familia, quae peculiari cuidam [ 36° ] c^iuam equationi fatisTaciunt, unam praeterea curvam opportune abfcondi, que a fimplici quadra- tura circuli dependeat, queque nobis conftrudionem pienam aptioremque impertiat, litque Temper in poteftate, dummodo y dentur per x, quanquam iepai aii indeterminate nullo pado ab invicem pof- fint. Qui rem hanc altius perfcrutari curabunt, non difficili labore intelligent in equationibus na- tur® bujus Temper includi curvam fimilem noflras limih modo detegendam. Cujus Tane methodi cognitio an utilitati & commodo Analysis Tutura lit in hujuimodi operofifiimis quasfiionibus Tolven- dis, non eiT cur diuiturniori oratione vobis exponam. T roperamus itaque ad rem noftrara. PROBLEM A. Tab. XIV\ Figura prima. Invenire curvam IM m ea proprietate donatam, ut ex dato pundo A duda in tangentem MT per- pendiculaii AG, intercepta MG lit Temper equalis con flan tia. * Ex pundo contadus M in axem APduc perpen- dicularem MP, eique parallelam infinite proximam mP' excita ex pundo M redam My parallelam Pp, dicque AP — x, Pp — M j= d x} PM =zy, ms—dy , & MG— a. Eiit Vdx' + dyd PT^= y^x a y^x — T y , — dy * 1 A — dy > TM — — 'ddx'+dy', ideoquc GT=iiAl * ' ms -f3 IVtfos. Traw. rot.J.m.TJKJ{ir.f>.36o. . jfy 3- [ 36i ] At propter fimilia triangula M sm, TGA, erit .. ... ; — . ydx — xdy % Mm : Mi : : TA : TG. feu V dxz q- dyz : ax : : — * y\Jdx--\-dy^ __ n ' unc^e fa(qa extremorum mediorum- dy ’ que multiplications, grit ad dx -\-dy zzzydy Arxdx, feu ydy ( od dx2, 4~ df _ X dx T" ^ Fac autem pro feparatione indeterminatarum x — confequenter dx^~, tumque hos valores pro x, & dx fubftitue in data asquatione. Habebis /, tdy ay a\fdr+az a * t tdy ady aydt & fadta differentiatione, erit — cddt r dy “Ht “i leu — ~v —aAdt f.a' + f.z y t.az + t* ty.cd 4" Cum porro ex nota Bernoulli methodo lit dt ' t tdt t.a' + e pone claritatis gratia hafce logarith- — . Hinc habebis — — — — y micas quantitates n n ty.a + Pofitis autem y — 7 = p atque ideo p y _ "1, & fafla harum quantitatum fubftitutj- dp — c?dt one, obtinebis — — ' •* /> npt.ar-\-t ~ a* dt , feu pofito videlicet jam primum n = eX & defcribe arcum minimum Ee , quern voca — du. Habebis z: a: : dx : du . ergo dx — ; quo valore fubftituto in fupe- riori aequatione dz^z1 — a1 = adx> haec mutabitur in iftam — — du, in qua infunt variables fe- paratae. Ut primum membrum ad formulas magis cognitas. reducatur, ita aequationem difpono z'lz^,z~— z=du-, 5C % turn conftituo AG=^-^ = /, fadtaque fubfti- . • t\lt . (fdt , ^ , tutione, onetur --7— — dt — -j-r— 4 = du. formula t a 1 *t a ut conftat, eft elementum arcus circularis, cujus radius — a , tangens =r= t. Ultima igitur haec aequatio ad conftrudtionem • perducit, quae circuli quadraturam fupponit. Centro itaque A, radio AI = a, defcribatur circulus ILP, cui fit tangens indefinita IK. Sumatur in hac tang- ente quaelibet IH = ty & agatur fecans AH = 2; fume praeterea differentiam inter tangentem IH, & ejus arcum IL, quae erit = z<;; tandem accipe arcum IL huic differentiae aequalem, & per pun&um E due AM 5= AH, pundtum M erit in curva quaeftta. Ex [ 365 1 Ex hac conftrudione facile colligitur curvam- noftram incipere in pundo I, turn ad modum lpiralis femper recedere a circulo, & infinitis circumvolutioni- bus ilium ambire. In pundo I curva tangitur re to. IA. Nuf addidi in mea con ftruft tone con ft a tem, propterea quod conftantis additio curvam non n utat. Nam IE vel fit aequalis u, vel u-\-b, vei tandem eadem prorfus curva enafcitur. Nunc vero font determinandae conftantes A & B, qua additai font in integratione, dum curva; redid-. cationem, & quadraturam invenimus. Quoniam d pofito s = 0, fit z — a, aequatio — — Aa — as, data, hac hypothe.fi, in iftam mutabitur ~ — Atf = o,unde: ■-S. A — -j quapropter aequatio completa erit 2> H Atqu.i 22 — aa—H. ergo ~ — Quod fpedat ad quadraturam, jam conftat fore aream AIM — o, cum fit 2 = radio, feu — a ; ergo — aa’J zz — aa /zdx .. . , — , evadit in hac aequatio a¥> ft- - * 2-’3,a hypothefi in iftam ati =0 : ergo aequatio completa efh t 3 s*zdx r , tx ts — / — . bed — — St ergo - 2-3-tf J 0 ■ 9/2 — aaV zz — 2.3 a . Zdx 2a _ ideoque fpatium I AM eft.tertia pars rec- tanguli ex AG, feu IH, & ex curva IM. Radium ofculi hac ratione definiemus. Ducatur* radius AR perpendicularis redae AG, & jungatur RM. Quoniam GM, AR aequales font, & parallels,' GA MR pariter aequales erunt, & parallels. Ergo 5 MR C 366 ] MR perpendiculars radio AR tanget circulum, 6c perpendiculariter occurret curvae Mm. Eodem pror- lus modo dudo radio A r normali reds A g, linea mr erit tangens circuli, & normalis curvae Mm. Igitur curva IM m ea eft quae nafcitur ex evolutione circuli, *& recta MR t= AG aequabit arcum cireularem IR. Quoniam vero RM=AG=IH, & IH ex con- ftrudione acquat duos arcus circulares IE, IL, arcus IR aequabit duos arcus IE, IL, & dernpto com muni IL, remanebit arcus IE = LR. Infinitefnnus fedor RM/«, quieft elementum areas REIM aqualis eft ** " ' ' ** ““ RMffl = ei‘ ~ ' c i i ■£,az ergo ■ 2a — - 2.3-fl .. t* 2-3 M ergo area REIM = IAM. Et ablato lpatio communi IEM, remanet fedor IAE=:MER. Addito autem fedore EAR fit fedor IAR = triangulo AMR, quod apprime cum veritate confentit; nam cum arcus IR = RM, conftat fedorem IAR aequare triangulum ARM. Curva tranftens per omnia punda G.g. erit bafts, ex qua gignitur tradoria YMm. Quaenam fit haac curva breviter videamus. Quoniam GA «, & MR«; funt fedores ftmiles, & AG = RM, erit Gn=.Mm ■~ds. Ergo aequatio ads—.tdt, erit aequatio curvae quaefitae, exiftente ordinata AG^:/1, Gn=ds. Ut autem aequatio reducatur ad arcum radii conftantis, vvocetur Tt—dw j erit t:a::ds : dw. Ergo ads=tdw . Ergo i [ 367 ] Ergo tdtzs.tdw, five dw=dt, five tandem Tt—gn',. quae eft aequatio fpiralis Archimedeae, cuj us conftrudtio ita peragitur. Age radium AP, perpendicularem radio AI, & fumatur arcus PQ^aequalis radio j turn polo A, de- fcribatur fpiralis Achimedea tranfiens per pundtum Q ; haec ipfa erit bafis, ex qua defcribitur tradtoria IM; prasdita tangente conftanti GM —a. Interea haec habe : fpiralis Archimedea eft ea curva, a qua tamquam ball noftra generatur tradtoria IMw. . Nunc fupereft animadvertere, quod fi in ilia formula, quam vir clariff. Vincendus Riccatus methodo motus . tradtorii conftruxit in fuo commentario de ufu hujus motus in aequationum difterentialium conftrudtione (ubi hanc methodum illuftravit penitufque abfolvit) fi, inquam, in ilia formula fupponas x 6c y efte coor- dinatas fpiralis Archimedeae, Sc y datas efle per x, quamquam indeterminatae feparari omnino nequeant, fufcipiet didta formula ex infinitis, quarum eft capax, unam quoque conftrudtionem depenaenter a noftra curva. Ea ex quatuor Riccatianis ibidem expofitis- formulis, quae hypothefi noftrae convenit prima, eft,, nimirum. abdz *Jbb-± qq qdx = bdy. Fadta ergo, ut dixi, fuppofitione, ejus x Sc y efie coordinatas fpiralis Archimedeae, fi infinita pundta N conftruendae curvae tuto invenire cupias, exigit ilia, methodus, ut defcripta tradtoria I.M m ope fiii, feu tangentis conftantis GM=#, fadto jam inotu «G verfus Q, tumque fumpta in axe quacumque conftanti . OS feroper ad eandem partem, fi per pundtum S, du.caa* r 368 3 ducas parallelam tangenti GM, donee occurrat or'di- natae OG— y in pundo N, hocce pundum, ut ihi demonftratur, eft femper in quaefita curva. Atqui vidimus fupra redam RA parallelam tangenti GM hujus noftrae tradoriae IM m fore perpendicularem 'fadio AG .fpiralis Archimedeae AQG. Figura 'Tertia. Ergo ut habeas infinita punda N.N. conftru- endae curvae, fufficit quod fumas femper in axe con- ftantes PG, PG=/> ad eandem plagam, tumque a pundis G, G ducas in radios fpiralis AM, AM produdos, ft oporteat, normales GN, GNj donee occurrant ordinatis PM, PM in N.N. Hoc modo obtinebis per infinita punda curvam hac methodo 'deferibendam. Invenies itaque hujufmodi curva2 ramum genitum a fpiralis arcu AMS die ANT j ab altero vero fpiralis arcu SMO die ANQj a tertio OMR efte ANV ; a quarto RK efle AY j a quinto denique KZ efte AW, & fie in infinitum aftympto- ticos omnes; ex quo propterea vides integram curvam, qu$ noftrae formulae conftrudionem fuppe- ditat in hac videlicet peculiari tradoria abdita ramis numero infinitis gaudere, ac eorum quemlibet votis 'fatisfacere rede pofte. Sed quia ad obtinendam didae formulae conftruc- tionem opus maxime eft ut abfciftaex fint in axe, earum vero ordinatae y fint omnes inter le parallelae (noftrae autem y hie funt ad focum) ac propterea oportet ut -eredem y datae fint per x, vel poftea feparari indeter- -'•minatae poflint, vel non, nunc ergo ut hifee conditi- onibus [ 3^9 ] onibus compleam, fatis mihi erit invenire squationem fpiralis Archimedes relats ad axem, quod fie affequor. Figura QtJARTA. Sit fpiralis Archimedea A/?zM, ejus axis FAF, ab»- fciffa AP = x, ordinata PM ad angulum redtum — y, eique infinite proxima pm . Dudta mo parallela ad axem, erit, mo==zdx, oM.=dy, Sit propterea AM radius fpiralis = t , cum quo Am faciat angulum infinitefimum MA m, Sc centra A, radio AM, defcripto circuli arcu mr> erit M r=dt. Voca arcum 7nr=ds, Sc eodem centra A, radio quovis conftanti — a, defcribe circulum Feb, Sc voca ejus arcum infinitefimum cb—du. Ex hac prsparatione erit primo AM = AP PM\ feu tx — Sc / = unde = xdx-\-ydy % z — z — - — z —/ ====. Prsterea habebis Mr -4 -rm =M;« feu Vf + y* 1 cif-{-ds7‘~dxzJrdy1. Sed ex fimilitudine Sedtorum Acb, Amr, eft Ac : cb : : Am : mr ; feu a\ dt : : t : ds. & ex squatione fpiralis Archimedes ad focum habes cb-=AAr, feu du—dt j unde erit ds~ Ergo fadtis opportune fubftitutionibus in altera fuperiori squatione, obtinebis df +dy%, feu tandem a' + tf + f X xdx + ydy Vol. LVII. x' + f : a' X dx'- + dy\ vel potius B b b d/Jf df 4- 2 d x dy X [ 370 ] atxy-\-x3y -f xy% — x*Jr xiy~ xzy1 +• y — rt'.v1 ^ **y -f- y. -a y ■«V “ 0 unde complete quadrato, 6c fadta radicis extra * J y a *• a J V a1 — z* tur 1 t* h fit. E. W. propofitam C 371 ] propofitam formulam. Sed (quod ei merito quidem in pretio eft) in irifinita harum curvarum familia unam irifuper latentem detegit algebraicam quarti. gradus, quas commode ejufdem formula conftruc- tionem fuppeditat, recfteque perficit. Nos in re fortafie difficiliori non diftimile exemplum hie attulimus. Vidimus enim problema noftrum, quod per tradtoriam fpiralis Archimedeae generatim con- ftruitur, expofeere & ipfum ad fui conftru&ionem curvas numero infinitas, fed quod moleftius videtur, magifque operofum, hujufmodi effe hafee curvas, ut nifi hypermechanico labore poflimus aflequi. Verun- tamen in infinito harum agmine facile 6c nobis fuit oftendere unam praeterea curvam abfeondi, quam illico affequaris dependenter a fola quadratura circuli, ideoque attenta rei difficultate, multo fimpliciori modo, quam initio fperare licuifiet. Noverim certe curvam hanc noftram non plene exhaurire datam for- mulam, fed infici nequit, ejufdem exhibere nullo fere negotio rediftimam, maximeque fimplicem con- ftrudtionem, quod fatis eft, aliifque planiorem viam oftendere, qua facilius enodare poftint hujufee generis quaeftiones inextricabiles primo intuitu, nec vero labore vacuas. Hoc itaque inventum credidimus non contemnendum fore, praefertim cum alias me- thodi ufque adeo note, quovis verfate ftudio, minime quantum nobis conftat, ad id commodum perducere valeant. Romas prid. Non. Ap;i!is, 1766. Pius Fantonus, Philofophus & Mathematicus Bononienhs. B b b 2 XXXV. A [ 372 ] XXXV. A Memoir concerning the mofi Wheels , etc. by Mr. Mallet of Geneva.. Communicated by M. Maty, M. D. Sec . R. S. Tranjlated from the French, by J. Bevis, M. D. R. S. S . Read March 26, 1767. § I.f" i t H E Stream of rivers is of fueh im- portance in moving machines of all kinds, that any attempt towards perfecting this part of mechanics may be confidered as of very- great utility. The firft wheel on which the Stream aCts is one of the molt eSfential members of the machine, and it is ealy to difeern that the greater or lefs effeCt thereof mull depend, in a great meafure, on the manner of constructing this wheel, and on the dimensions given to it. I Shall not at prefent inquire whether wheels of different constructions from thofe which have been long in ufe might be advantageoufly Sub- stituted in their Stead ; but confine myfelf, in this effay, to an examination of the moft common ones, and to discover the means by which they may be made to produce the greatest poShble effects. Their construction is very Simple ; they confiSt of feveral planes inferted into the fame axle placed horizontally above the furface of the water, and in a polition perpendicular to the Stream. Thefe planes, called 3 -s fynJt ft. .[ 373 1 jl)at-boards> by yielding to the adion of the dream, Caufe the axle on which they are fixed to turn round, by means of feveral wheels, which take into each other, and give motion to the part deftined to pro- duce fome purpofed effed, as the mill-done in a corn- mi 11. The fize of the float-boards, the velocity with which the wheel is to turn, and the number of the float- boards to produce the greatefl poffible effed, are three main things I propofe to examine in the following inquiry. In the fird place I will fuppofe the total refinance which this wheel has to encounter, on the part of the machine, and which hinders it from moving fo fwift as the fir earn, to be exprefled by a weight tt, fufpended to the extremity of a cord fixed to the cir- cumference of a wheel whofe radius is d, and which has the fame axle as the float- board wheel, fo that the effed of the dream is to raife the faid weight sr„- as exprefled in Tab. XV. fig. i. I will likewife fup- pofe, that the dream, by its velocity, moves through v feet in one fecond of time, and that this velocity is the fame, though at different depths. § II. After thefe fuppofitions, the firfl; thing that prefents, is to determine what fhould be the fize of the float-boards for the dream to be capable of railing the weight n r. with a certain determinate ve- locity. Let A A BB, jig. 2. be one of the float-bords let into the axle AA, and placed vertically in the water, fo as to receive the perpendicular impulfe of the dream. Its horizontal length BB— (3 feet, its vertical height AB=i« feet, the velocity of the wheel [ 374 ] wheel at the point B, fuch that it fliall run through z, feet in a fecond ; n pounds the weight of a cubic foot of water ; and I will fuppofe the impulfe of the ffream on a plane perpendicular to it is (as Dr. Da- niel Bernoulli has hated in his Hydrodynamica ) equal to the weight of a prifm of water, whofe bafe is the plane, and its altitude the generating height of the velocity with which the plane is impelled. This being fuppofed ; let AP— x, P/>, its differential, ■=dx, which will give the velocity of the float-board at the point/*— -z, and the relative velocity of the ffream with which the plane is impelled at the fame point — v — - z whofe generating height is — — . feet, whence we have the weight of the parallelo- piped of that height, and of the bafe PP pp equal to - (— v-z)z pounds, which weight multiplied by the length A P (x) of the lever which tends to turn the plane, will give — - z / for the total effedt of the flream on the little rcdtangle PP />/*, whofe integral is (vvxdx — — — ^ xxdx x% dx) n_& ( 60 \ 60 / V'UXX 2 .x* .x - vz — y-' zz ~ •i vvff-^-vz. ) (putt'ng A C —f for the iliftance be- tween the axle and the furface of the water when the floats board has only its part CB plunged in the water) which (putting x = a) will become - ( ^nv---oz-\-^zz.a»—ivvfJ + - — » z [ 375 3 *-— ) and will exprefs the effedt on eta, ' * the whole plane CC BB, equal tt d, the produdt of the weight 7r by the length d of the lever on which it adts in oppofing the motion of the wheel. § III. If the wheel be plunged as deep as its axle, that is, f — o, the equation is changed into this »|3 a. ctf 2 “ U :W — -VZ +• 4 ~ d7r, where it appears 1°. That the quantities d, tt, v and js remaining the fame, we have (3 inverfely proportional to the fquare of a, whence it follows, that if the length (2 is to be diminished without altering the effedt of the float- board, the height a muft be encreafed proportionally to the fquare root of jG ; for example, if (2 is to be made four times lefs, it will be fufficient to double the height u. 2° That likewife the velocity of the float-board remaining the fame, the weight tt will be in the compound ratio of the length (3, and of the fquare of the height uot. 30 Without meddling with the dimenlions of the float-board, the more the quantity 2; is increafed, the more muff the weight 7T be diminished. If z be made = 0, we have TT— •£— ±vv, and ifs— v we have 77-= vv. that is fix times greater than in the fil'd cafe ; which is very conformable to the nature of things, for when the wheel is-in motion, the Stream then not adting upon it but with the excefs of its velocity above that of the wheel, it follows, that the greater fuch velocity is, the more will the effedt of the dream be diminished. [ 376 ] It follows from our laft remark, that the greateft weight with which the ftream can conftitute an equi- librium, will be = but then the wheel will 3 I20d not have any motion, nor confequently the weight 7 r : If the float-board be increased, or the weight diminifhed, from that inftant the wheel will begin to turn, and the fwifter as the float-board is greater, or the weight lefs ; but in moft machines, it is required that the weight may be the greateft poflible, as alfo the velocity with which it is raifed. A queftion therefore here offers itfelf, whofe folution is of much importance. What muff be the velocity of the float- board whofe dimenfions are given, that the product of the weight by its velocity fhall be the greateft poflible ? § IV. The velocity of the weight tt is - z feet in a fecond, which being multiplied by the value of ±vv — ivz + ±zz) will give the pro- dudl vz — ~2VZZ t z) which muft be a maximum ; for which purpofe make i. wdz — +vzdz -f- ^ z% dz = oj whence we have z ~ 8 ~ ^ 10 = 0,5 3 75 2^ : this value of # being fubftituted,make the equation '-*uv II 4- 2 -v/ io zz /3ax ” 8i 11 + 2 \/lO 4860 vv, fo that we have the equation d nr nvv + rt dw 200,520 , ' ' nvv * which expreffes the dimenfions of the float-board where the effed will be the greateft poflible. If the float-board be plunged no deeper than to CC, as we ihave at firft fuppofed, the molt advantageous value of of z may be determined in the fame manner, which will be found j,4_sa/'!_Ji/ r 37* 47 • 1 1 yAfTA 1 + 1 °f 6 a, - 9 ( a 4 fA) If f — o, this value of £ — 0,537a; /= °>25 * /— 0,3 / - 0,5 a r f~ 0,7 a /=■ 0.9 * /=« r CS a — 0,49 vu =. 0,486^ — 0,436a; r:~ 0,3Q0a; = °>353^ = °>333rJ By the infpedion of thefe different values it ap- pears that this value of z diminifhes as the plunged part is greater, and that this velocity can never exceed the quantity 0,537x9 nor be lefs than L.v *. This value of z and of its fquare zz being fub- flituted in the general formula (§ II.) we fhall ob- tain from it the following equation : M *6-27 « 4 r*+i i/«+* («*-*//) v- rott4;4nf-— 8 I (a +— -f +) which for a given relation between f and a will fhew the breadth 0 for producing the greatefl efteft. * If in the value of z we make f — «, we have z — - which obliges us to take, according to the common method, the differentials of the numerator and of the denominator, confi- deringy as variable, and the relation of thefe differentials will give the value of z : but on account of the radical quantify, the calculus being fomewhat tedious, and, again bringing out 3 — ^ and that after fevcral fimilar operations, it is better to have re- courfe to the equation from which the value of z wu; deduces ; ... 1 — r this eouation is | »vz.— — -2- axvv. — * cc / CC i ■r * , «4+ +/; by the above operation will be | zz'zz vz — } vv, and .. LV1I. c c c which : ' v. . i As [ 373 ] As the extremity of the float-board muft have a certain velocity depending on the relation of the height a to the plunged part, and as the velocity of the weight rr — - z, it follows that if we would in- ° a creafe the velocity of tt, we mud diminifh the height a and increafe the breadth ft, fothat the product /3 exa, and the relation of j to a. may be the lame as before ; for example, if the wheel be plunged as deep as the axle, to double the velocity of the weight, the height of the float-board muft be reduced one half, and its breadth be quadrupled. § V. It may fo happen that the channel on which the wheel is placed (hall be fo (hallow and narrow, as not to allow the float-boards the neceflary dimen- fions, for raiflng the weight with a convenient ve- locity. In this cafe we are obliged to raife the axle of the wheel above the furface of the water, fo much that the lever on which the dream adls may be long enough to recompenfe the fmallnefs of the float- boards. Herein it is neceflary to folve the fol- lowing problem : The breadth b, and the height a, of the float-board AB being given ; to find the radius CA (r) of the wheel which fhall caufe the weight 7r to afee-nd with the velocity z. The exaft folution of this problem might be de- duced from the formula (§11.) which would render the operation tedious, the equation being of the fourth degree ; but it may be rendered far more Ample by a Juppofition which is but little wide of the truth when AB is but fmaflin companion of CA, and this is to con fid er [ 379 ] confider all the points of the float-board AB as affedted with the fame velocity z. n b Let C P fig. 3. = x, we fhall have — (*u— z)% f. xdx nb for the eftedt of the portion AP, and — zj* X - - for the effiedt of the whole float-board AB. 2 This quantity mu ft be made equal to d?r, and then, juft as in the foregoing cafes, fuch a value of 2; be fought, that the weight sr and its velocity may be the greateft pofiible ; that is, the differential of z (v — z)z muft be made — o, which gives z ■== 1. v. There- r , ' tiabvv . . , . 2/Odw — naabvv fore d 7T = ( 2 r~\-a ), and r— 7 , 270 1 ' onabvv 3 and the velocity of the weight tt will be =* 2 n cl a b v v V V, 8lod 7 r + aav § VI. We have feen that the calculus was much Amplified by fuppofing one of the velocities conftant for all points of the float-board. For this velocity being c, the effedt of the whole float-board will be fimp'y r0 (vcy acc ■ff It will therefore not be unufeful to inquire what this velocity c muft: be, that the effedt of the float-board may be the fame, as fuppofing, as we have hitherto done, a variable velocity, and proportional to the diftances from the axle, we have only to make ^ — c (— — ) n@/ , rjr. «3 — f* -rJ ivviza-fD-^vz—— 2 ~4-/ 4 ‘ CC / IV.'lbut the equation whence we got the value of 2; C c C 2 (S IV.) [ 3® ° ] (§IV.) > ^ fhall have c 4 vz u3 3 « •/3 ■r -V A *2. ** -f ff a,cc — o, we = v-VAvv- 4- zz. «« + ff oc ct If/— O, we have ss = 0,2881; w and c = 0,345-j f=^* zz — Oyigovv c — 0,3361; j — ct zz = fvv c = fv. fo that whatever be the relation of f to a, the velocity c is ever nearly — 4 v, and the more exactly fo, as f is greater. Wherefore we may always aflume _l_. n@.vv. (aa —ff) — d 7r for the effect of the flream upon a float-board whofe plunged part is u — f; this etfed will be increafed in the ratio of 4 to 9, when the wheel has no motion, for making c — o, we find it — n@vv. (a cl — ff). § VII. Hitherto we have all along fuppofed, that the float-board did through its whole plunged part receive the perpendicular impulfe of the flream ; but it is eafily underflood, that the wheel coming to turn, prefents to the flream the plane of the float- board under an angle which is continually varying, which diminifhes its eflfedt every inflant, as it removes from the vertical : This inconvenience may be remedied by multiplying the number of the float-boards, fo that when the firfl is removed from the vertical as far as a certain point, the next may occupy that advantageous place, to he in its turn replaced ibme time after by a third, and fo on. Now our third inquiry is, to aflign the angle contained between two float-boards, or, which comes to the fame, the number of float- boards the wheel fftould confifl of, that its eftebt may he the greateft poflible, being of no lefs importance than the preceding ones. To begin then with the molt Ample C 381 ] Ample cafe j we will fuppofe the wheel immoveable, or that c o, and proceed to inveftigate, whether, fuppofing the number of float-boards to be greater, the ium of the effects will come out greater or lefs than what refults from one fingle float-board placed vertically. In order to a general folution of this queftion, we will fuppofe two float-boards CD and CE fig. 4, making any angles with the vertical, and let us com- pare the effedt of the fingle float-board GD with the effect refulting from the float-boards FEand GD taken together, which will be reduced to FE and OD, becaufe the part OG becomes ufelefs, as the ff ream is intercepted by F E. Let CB — CD — CE a, CA =f colin. BCD = m, cofin* BCE = [Ay which gives CG - CF=^ and m y. CO — ^ a. Then we fhall find, by § VI, the effedt of G D ~ — - --- (tn muu — ff) that of O D tl&VV . . . . — q " {mm act — fiftctu). and that of FE — ~j~ {ft ft act — ff)', whence it appears, that the fum of the two laft is exadtly equal to the fir ft, which will ever hold good whatever be the value of/. Whence arifes the following theorem : Whether the wheel he plunged quite up to the axle, or only in part jo, provided it be immoveabUy and that one of its jhat-hoards be placed vertically , its ejfeffi will be cgh- Jlantly the famey whatever be the number of float-boards oppofed to the f ream, even though it were infnite. The f 382 J The latter part of this theorem, though flowing from the general demonftration, may be alio demonftrated, immediately, in the following manner ; Let BP ng. 5. be we have MO ad x a — x 7cc* X -f a * __ L/. ,and CO- 5 a — - la? dx -f 2 &axd x CO # a — 2 x X -f x x neglect- ing the dx) and a 05 — CO 2 aaX dx OL—V ; Therefore the effeCt of the ffream upon OM, which is rt$vv 120 . (aci * \ c P . n(Svv , CO/ — will become — — — (20^ — CP 2 xdx) whofe integral is ? 0 V V I iO (2ux — xx) where- in puttting x = « — /, we have -//)for the total effed of the ftream upon the wheel, which is the fame as that of a Tingle float-board A B in a vertical pofition. „ , , , - . k VIII. This theorem will alfo hold true for the cafe of § V. wherein we have fuppofed the height of the float- boards very fmall, in companion of the radius of the wheel; we havefeen that the effeCt of a {ingle float-board placed vertically was — nabw f2r -V- a) ; the demonftration of the preceding § wi be applicable here after the fame manner, and will {hew that whatever be the number of float- boards, the effeCt will be ever the fame. It does not however follow that the number of float-boards fhould be indifferent; for the wheel coming to turn the float-board, its lower part, which received the perpendicular impulfe, will no longer n receive [ 383 ] receive it other wife than obliquely, ana the effect vCdd diminifh till the angle formed by two neighbouring float-boards be bifeded exadly by the vertical, which will render the firft entirely ulelefs ; arter which the effed will increafe anew, and will become again greateft, when the lecond float-board is got to the vertical j fo that in order to fix upon the mod; ad- vantageous number of float-boards, regard mufl be had to the fum of the different effeds for all the lituations of the float-boards during one whole turn of the wheel. Whence it follows that in this cafe, wherein they are fuppofed very fmall, the greater their number is, the greater will be the fum total of the effeds, fince, if that number were infinite, there would be a float- board in a vertical pofition every inftant. . § IX. This will no longer hold good, if the height of the float-boards be mote confiucrable, and it be found neceflary to take the different velocity of their different points into confideration ; by com- paring (fig. 4-) the preffure on FE with that on the portion GO, they will he found no longer equal, pas in the foregoing cafe ; it is true that the fame quantity of fluid ads on thefe two planes, and the di fad van- tage which FE has by receiving the impulfe more obliquely, is exadly compenlated, as before, oy tnc length of the lever,, but the difference ariies from tne different velocity of the correfponding points of b E and GO 5 thofe’velocities are in the ratio of CT to CG, or as cof. ACG to cof. ACE, which fhews that the effed of FE is always lcfs than that cn GO, and confequently the effed mud be dimi- nifhed, by adding a greater number or fioat-boaids 5 [ 3§4 ] the faid effect will be greateft when there is only one float-board placed vertically, and lead: when their number is infinite : let us enquire what it will be in this latter cafe. We will fuppofe the fame fig. 5, and the fame denominations as in § VII. We had CO = we fhall have (neglect- ing dx \ dx\ and dx 4) aa — CQ — 2*.ec?x , a — X CO j a. ' — CO Actctd X -\T .1 r , and — ± . Now the pref- « cc fure on OM is, by § II n $ a. — ( T T A /y /v ' 120 ««■ CO + i. 33 VV ( aet 4 C O ') •* —J a* ^ -CO)-S2.i 3 which (by putting for C O its value) will become (2 c&dx — 2 xdx) (v — z~) whofe integral »/? 120 *9 (2 ccx — x x) (v — n@ (v — z7) 120 ' ' 1 x 120 (making x r= a. — f) will exprefs the efleCt re- fulting from an infinite number of float-boards : this lead effeCt will be to the greated, that is when there is but one float-board, as ( v — z~) : vv — * 4- 4- — (act 4- //) or as (a; — x ) 3 » 0,0. — jf I a a « ' ' JJ J \ / : 4. vv - i zz. (~r-J §• VI. This ratio will be that of 1 : 2 iff = o 1:1,485 f = la 1 : 1 f =■ * §X. If [ 385 ] § X. If we take nothing but the inoft advanta- geous pofition into conftderation, and preferve the greateA effect entire, it follows that the angle BCD (fig. 6.) between two float-boards mud be fuch that E (hould enter the water at the inflant when AB quits the vertical, fo that the coflne of that angle be = -j in confequence of which the following table may be conArudted, (hewing what the number of float- boards (hould be for a given ratio between f and a. r 4 float-boards, we have/' 0, 5 0,3090a 6 0,5000 a 7 0,6236a 8 0,7071a 9 0,7660a 10 0,8090a 1 2 0,8669a 14 0,9009a 16 0,9239a 3 8 0,9397a 20 0,9510a &L\ &c. § XI. Certain authors treating of hydraulics, have in this part thereof given the fame table, as containing the true number of float-boards the wheel (hould confiA of: but we have feen upon what prin- ciple it was formed, and that it was only to preferve entirely the effect of the vertical float-board ; from whence it follows not that the number of float- boards which it afligns (hould be the moft advanta- Vol. LVII. Ddd geous. [ 386 ] geous. To which purpofe the effedt produced from every pofition of the wheel, and for the different number of the float- boards, fhould be computed ; the number which gives the arithmetical mean be- tween all thefe effedts, the greateil of all, will be that to be chofen, and preferred before what the above table indicates. It may be fufficiently fatisfadtory to compute only the effedt from I to io degrees. Thus, for example, for the wheel entirely plunged, we are to find the effedt (fig. 7.) i° oh OA, 2* on OI and gb, 3°on OH, and fc, 4* on OG and hd , 50 on OF, and pe, 6° on OE, 70 on OD, 8° onOC, and 90 on OB. After which the wheel returns into the fame pofition it had at firft • and we are to divide the fum of all thefe effedts by 9, to get the arithmetical mean. We will next fuppofe the number of fix float- boards for the fame cafe of f = o, and compute the following effedts. i°onOG-|-tfA, 30 on OE 4- 7/ c, 5° on OI -j- 2° OF 4- mb , 40 OD 6° OH-(-/3B. The fum of all thefe effedts divided by 6 will give the effedt of the wheel of 6 float-boards. The fame thing, fuppofing the angle 40 degrees, or 9 float-boards, and as after a revolution of thefe 40 degrees, the wheel returns into a fimilar pofition, the fame mufl be divided by 4. Then for an angle of 30 degrees we are to divide by 3, and fo on* for [387 ] . . I have made this computation to great exaiftnefs, for the cafe of / = o, / — 4. #, and /= o, 866 a. = a co f. 30° 3 the refult, 10 If/= o. for 4 float-boards, the arith. mean = 0.33 c (»-e- n 13 a. aw). It may be obferved in this firft cafe, that there is fome advantage in taking 6 float-boards inftead of 4 fhewn by the table j the effedt will be increafed in the ratio of 100 to 1 18, and yet will be more than about of the greateft effedt above calculated for a Angle vertical float-board } fo that the found di- menfions muft be a fmall matter altered, and the quantity (3 a ci increafed by-1-. for 6 =0,396 (&c, = °>336 (^* = 0,323 (&V. = 0,295 (&c. = 0,214 (Off. 0,277 (&v» 0,281 0,285 (&V* 0,284 (&V. 0,276 (&c. 0,238 (£fc. In this fecond cafe 9 float-boards are to be taken inflead of 6 fliewn by the table, though the differ- ence will be but very fmalb and we fliall have an effedt which will be T8_0%i of that of a ver- tical float-board, and in that ratio that the quan- tity /3ct a found by the above formulas, muft be in- creafed. * 3° if 9 32 lS an infinite number 2° If f = 4 for 6 flo. 7 w 9 12 1 8 an infinite number D d d 2 [ 388 ] 3® If/ =1 o,866 * for 12 fl. = °>°99 (&Ct i8 • = 0,099 (Gfc. g6 = 0,104 i&c- an infinite number = 0,103 In this third cafe the difference is ffili very fmall, and the effect refulting from 36 float- boards will be of the effect of a Angle vertical float- board. XXXVI. » [ 389 ] XXXVI. A n ew Method of confruEling Sun - Dials, for any given Latitude , without the Ajjiflance of Dialing Scales or Lo- garithmic Calculations . By James Fer- gufon, F. R. S. Read July 2, | AR A W the flraight horizontal line 1767 ; JJ BAD Tab. XVI. (fig. i.) of any convenient length, and on the end D thereof raile the perpendicular DE. BifeCt BAD at A, and draw the right line ACE, making the angle EAD equal to the latitude of the place for which the dial is to ferve, as fuppofe 510 4. for the latitude of London. Draw alfo the right line FC D, making an angle at D with the horizontal line BAD equal to the co-latitude of the place, or height of the equinoctial. So, FCD will be per- pendicular to ACE, BAD will be a horizontal plane feen edgewife, D E a vertical plane, FCD the plane of the equinoctial, and ACE the axis or ftile of the dial 3 the whole triangle ADE repre- fenting the whole broad plate or ftile. Around the interfeCtion C, as a center, with the radius CD, defcribe the circle F6D6F, and divide its circumference into 24 equal parts, beginning at D or at F. Then conned: all the points of divifion, which are equidiftant from F, by the flraight lines i ti, 2 10, 3 9, 4 8, &c. continuing as many of 4 thefe [ 399 ] thefe lines as are needful to the horizontal line BAD, and to the vertical line DE. Continue E D down to d (fig. 2.) and draw bd parallel and equal to BD. Draw alio the right line A eca , from fig. 1. to fig. 2, and that the line will be perpendicular to the line bd in fig. 2. cutting it in thq middle point c. From fig. 1 . take C F or C D in your compafles ; and in fig. 2. fet that diftance from c to e upwards, and from c to a downwards, on the right line Aeca. So eca in fig. 2. fhall be equal to FCD in fig. 1. and bed in fig. 2. Ill all be equal to BAD in fig. 1. On thefe two lines bed and eca make the ellipfis bopqr> &c. according to the common rule for de- scribing an ellipfis upon the tranfyerfe and conjugate diameters bed and eca. Then, from thole points in the horizontal line BAD (fig. 1.) where the right lines. 1 ii, 2 10, 39, &c. meet it, as at d, e, f gt b , A, /, k, /, tn, n, draw the right lines do, ep, fq , gr, &c. quite through the ellipfis, and all par- allel to the right line Aeca. Then, from the mid- dle point c of the ellipfis, draw right lines to thofe points of its circumference where the forefaid parallel lines cut it; and they fhall be the true hour-lines fop a horizontal dial ; to which fet the hours, as in fig. 2. Laftly, in fig. 2. draw cy parallel to ACE in fig. 1. and cy fihall be the axis or edge of the lfile cdy that calls the fhadow on the time of the day. The horary fpaces, or angular difiances of the hours on the dial, being thus found, there is nooc- cafion for confining the hours thereon, or the lengths of the hour-lines, within the ellipfis ; for they may be C 39* 3 produced beyond it to any diftance, and the hour- letters placed in a circle, as in fig. 4. A geometrical method for defcribing the whole or half an elliplis will be (hewn further on. From fig. 1. contiue out the horizontal line BAD to any length, as to XII in fig. 3. Then, .from the points *** in the perpendicular DE (fig. 1.) where the parallel lines 5 7, 4 8, 39, 210, and 1 11 meet it, draw the right lines H, I, K, L, M, N, all parallel to the horizontal line BA DP XII. producing them at pleafure : and, in fig. 3. draw G XII parallel to DE in fig. 1. This done, take CF or CD (fig. 1.) in your compaffes, and fet off its length both ways from G ('fig. 3.) to VI and VI, on the right line E H VI G VI. So VI G VI in fig. 3. fhall be equal to FCD in fig. 1. and XII G in fig. 3. ill all be equal to DE in fig. 1. On VI G VI as a conjugate diameter, and G XII as a femi-tranfverfe diameter, defcribe the femi-ellipfe VI, VII, VIII, IX, &c. and, to thofe points of it where the parallel lines FI, I, K, L, M, and N cut it, draw the right lines G VI, G VII, G VIII, G IX, &c. as in the figure j and they will be the true hour-lines for an eredt diredt fouth dial : and they may be produced beyond the ellipfis, and li- mited either by circular or fquare lines, between which the hours may be placed. Laftly, drawPG in fig. 3. parallel to AC E in fig. 1. and P G will be the axis or edge of the ftile P XII G for calling a fhadow on the time of the day. And thus, by means of fig. 1. conftrudted for any given latitude, either a horizontal or vertical dial may be made for that latitude. If [ 392 ] If you want a fouth dial to incline by any number of degrees, as fuppofe 16, draw the line Dz, making an angle of 1 6 degrees with the perpendicular DE, in fig. i. Then Dz (hall be the femi-tranfverfe axis of the ellipfe, and C6 the fern i- conjugate : and right lines drawn parallel to DP XII quite through the femi-ellipfis, from the points *** in D.z, where it is cut by the parallel lines 5 7, 4 8, 3 9, &c. fhall cut the femi-ellipfis in thole points through which the hour-lines muft be drawn, as from G in the upright fouth dial, fig. 3. If vou want to make a reclining fouth dial, draw the line DH (fig. 1.) making an angle with the per- pendicular DE equal to the intended angle of recli- nation, and produce DH and CE till they meet. From D to that meeting, will be the length of the femi-tranfverfe axis of the ellipfe, and from C to 6 the length of the femi-conjugate : which being found, proceed in all refpe&s as above for the- fouth upright dial. To draw the ellipfis, and find the hour-points in it, cbferve the following method. Fora horizontal dial, as fig. 4. Make the radius AK of the circle BKDL equal to AD in fig. 1. and crofs the circle at right angles by the two diameters BAD and KAL, and divide the circle into 24 equal parts, beginning at B. Conned: thele points of divifion, which are equidiftant from B, by the right lines afi bg, cb , &c. all parallel to KAL, as in the figure. Make the radius AG of the circle FGHI in fig. 4. equal to CF in fig. 1. and divide FGHI into 24 equal parts, beginning at I. Then through thele points [ 3g3 1 points of divifion, which are equidiftant from T, draw the right lines 7 5, 8 4, 9 3, jo 2, &c. till they meet the former right lines, ek , di, ch , &c. in the points 7.5, 84, 93, 10 2, and 11 1, on both fides of the diameter BAD ; all which points are in the elliptical curve, and it is to be drawn through them, by hand, as in the figure. And right lines drawn from the center A through thefe points in the ellipfis, will be the true hour lines for a horizontal dial. To draw the ellipfis for a vertical fouth dial, make DE (in fig. 1.) the radius of the largefi; circle, and CF the radius of the fmalleft : the diameter of the former gives the tranfverfe diameter of the ellipfis, and that of the latter gives the conjugate : which being found, conftrudt the ellipfis the fame way for the vertical dial as above {hewn for the horizontal ; then draw the hour-lines in the lame manner, from the center of the dial, through thofe points of the ellipfis where the interfeclions of the crofs-lines meet it, as in the horizontal 5 and the thing will be done. Vol. LVII. E e e XXXVII. [ 394 J XXXVII. On the Formation of Iflands . By Alexander Dairy mple, Efquire. Com- municated by C. Morton, M. D. S, R. S, Received May 4, 1 767. Read July 2 ■ SHERE is not a part of natural !?6/‘ hiftory more curious, or perhaps to a navigator more ufeful, than an enquiry into the formation of iflands. The origin of iflands, in ge- neral, is not the point to be difcuffed ; but of low, flat, iflands in the wide ocean ; fuch as are mod of thofe hitherto difcovered in the vaft South- fea. Thefe iflands are generally long, and narrow; they are formed by a narrow bar of land, inclofing the fea within it ; generally, perhaps always, with fome channel of ingrefs at leafl: to the tide; com- monly, with an opening capable of receiving a canoe; and frequently fufficient to admit even larger veflels. The origin of thefe iflands will explain their na- ture. What led me firft to this deduction was an obfervation of Abdul Roobin, a Sooloo pilot ; that all the iflands, lying off the N.E. coaft of Borneo, had fhoals to the eaftward of them. Thefe iflands being covered to the weftwrard by Borneo; the winds from that quarter do not attack them t 395 3 them with violence. Bat theN.E. winds, tumbling in the billows from a wide ocean, heap up the coral with which thofe Teas are filled. This, • obvious after dorms, is perhaps, at all other times, im- perceptibly effected. The coral banks, raifed in the fame manner, be- come dry. Thefe banks are found of all depths-, a't all didances from fhore, entirely unconne&ed with the land, and detached from each other : although it often happens they are divided by a narrow gut, without bottom. Coral banks alfogrow, by a quick progrefiion, to- wards the furface ; but the winds, heaping up the coral from deeper water, chiefly accelerate the forma- tion of thefe into fhoals and iflands. They become gradually fhallower ; and, when once the fca meets with refiftance, the coral is quickly thrown up by the force of the waves breaking againft the bank} and hence it is that, in the open fea, there is fcarce an inffance of a coral bank having fo little water, that a large fhip cannot pafs over, but it is alfo fo fhallow that a boat would ground on it. I have feen thefe coral banks in all the ftages j fome in deep water, others with few rocks appear- ing above the furface, fome juft formed into iflands, without the lead appearance of vegetation, and others, from fuch as have a few weeds on the higheft part, to thofe which are covered with large timber, with a bottomlefs fea, at a piftol fhot diftance. The loofe coral, rolled inward by the billows in lage pieces, will ground, and the reflux being un- able to carry them away, they become a bar to co- agulate the fanch always found intermixed with E e e 2 coral } C 396 ] coral j which fand, being eafied raifed, will be lodged at top. When the fand bank is raifed by violent dorms, beyond the reach of common waves, it be- comes a refling place to vagrant birds, whom the fearch of prey draws thither. The dung, feathers, 6cc. increafe the foil, and prepare it for the recep- tion of accidental roots, branches, and feed, caft up by the waves, or brought thither by birds. Thus ijQands are formed : the leaves and rotten branches, intermixing with the fand, form in time a light black mould, of which in general thefe iflands confiff, more fandy, as lefs woody ; and when full of large trees, with a greater proportion of mould. Cocoa nuts, continuing long in the fea without lofmg their vegetative powers, are commonly to be found in fuch iflands ; particularly as they are adapt- ed to all foils, whether fandy, rich, or rocky. The violence of the waves, within the Trcpicks, mud generally be directed to two points, according to the monfoons. Hence the iflands formed from coral banks muft be long and narrow, and lie nearly in a meridional direction. For even fuppofmg the banks to be round, as they feldom are when large, the fea, meeting mod refidance in the middle, mud heave up the matter in greater quantites there than towards the extremities : and, by the fame rule, the ends will generally be open, or at lead lowed. They will alfo, commonly, have foundings there, as the remains of the bank, not accumulated, will be un- der water. Where the coral banks are not expofed to the common monfoon, they will alter their dire&ion ; and [ 397 ] and be either round, extend in the parallel, or be of irregular forms, according to accidental circum- flances. The interior parts of thefe iflands, being fen, fometimes form harbours capable of receiving veffels of forne burthen, and, I believe always, abound greatly with fifh ; and fuch as I have feen, with turtle-grafs and other fea-plants, particularly one fpecies, called by the Sooloos Gaimmye, which grows in little globules, and is fomewhat pungent, as well as acid, to the tade. It need not be repeated, that the ends of thofe iflands, only, are the places to expedt foundings: and they commonly have a {hallow fpit running out from each point. Abdul Roobin’s obfervation points out another circumdance, which may be ufeful to navigators ; by confideration of the winds to which any iflands are mod expofed, to form a probable conjecture which fide has deeped water; and from a view which fide has the fhoals, an idea may be formed which winds rage with mod violence. XXXVIII. Am [ 398 ] XXX V III. An Attempt to determine the Height of the Sun s Atmofphere from the Height of the Solar Spots above the Suns Surface : In a Letter to Mr. J. Ellicot, F. R. S. from the Rev . Mr. Horfeley. F. R. S. 'Rea^;-^,y 9>1 Return you many thanks for your 1 obliging communication of the obser- vations of the late tranlit of Venus hy Mayer and Rohlius. The phenomena which they relate of the atmofphere of that planet are highly curious. They were perhaps the more iriteredirig to me, as they confirmed fome conjectures of my own, concerning the great height of the atmofphere of the fun, and of thofe of the two nearer planets. I once attempted to make a rough companfon between the height of the fun s atmofphere and that of our own, hy com- paring the height of the folar fpots above the furface of the fun with that of our clouds above the furface of the earth, which I did in the following manner. The inclination of the Sun’s equator to the place of the earth s orbit is fo fmall, that in this enquiry I think it may fafely be neglefted; and I confider the two planes as one. LetT be the center of the earth, S that of the Sun. Join T S, and let dej "be a great circle of the fun’s fphere, formed by the interfedtor of the plane of the earth’s orbit with the fun’s fur- i face. [ 399 ] face. Let ABC be the circle defcribed by the revo* lution of a fpot. From T draw Ty’and TV touch- H! ing the circle def in f and d, and cutting ABC, in C and A. Join df; through S draw HSG, parallel to df Join SC, SA, S d. The fpots are hid be- hind the fun three days longer than they are vilible. That is, they are hid 15 days, and are feen only 12. The earth’s motion in 15 day is 140 17'. The fpots traverfe the like area in id. oh. 50' nearly. Hence, if the earth flood flill, the fpots would be hid only 13 d. 23 h. 1 o', and their whole fidereal period being 23d. 5h. they would be vilible 1 1 d. 5I1. 50', and the time of their occultation would exceed the time of their appearance by 2d. iyh. 20'. Hence the arc AC is lefs than the arc ABC, by the motion of 2d. iyh. 2 o', that is, by 38° 52' 56". And the femi-circle being a mean arithmetic between A C and ABC, AC will be lefs than the femi-circle by half as much; that is, by 19° 26' 28". Hence each of the angles GSA, HSC is 9°43' 14T The angle bsd-=.d TS = 16' 1" 27"'. Therefore dS A is 90 27' 12". Hence S A — 1,013767 fuch parts as > Sdis 1 . The [ 4°o ] The diftance therefore of thefe fpots from the center of the fun is 1,013767 femi-dia meters of the fun, and their diftance from his furface is in in de- cimal parts of his femi-diameter ,013767. Hence it is evident that the height of the folar fpots above the furface of the fun, is above 54 fuch parts, as bear each to the fun’s femi-diameter, the proportion of one Paris mile to the femi-diameter of the earth, which is that of 1 to 3923 nearly. The height of our atmofphere is generally reckoned about 50 miles. That of the lighted clouds fall fhort of one mile. The whole height of our atmofphere there- fore is, at leaft, 50 times that of our high eft clouds. It the whole height of the fun’s atmofphere bear as large a proportion to the height of thele folar fpots or clouds (and I think the proportion is likely to be much larger), the height of the fun’s atmo- iphere is not lefs in proportion to his femi-diameter, than 54 times that of the earth’s, and exceeds two thirds of his femi-diameter, being in decimal parts thereof ,68835. The probability feems to be that the height of the fun’s atmofphere is almoft double of this; for I queftion whether the mean height of our clouds exceeds 4. a Paris mile. The folar fpots, therefore, are 108 times as high in proportion ; and then, fuppoling as before, that the whole height of the fun’s atmofphere bears the fame proportion to the height of his fpots, as the whole height of our at- mopfhere to the mean height of our clouds, the fun’s atmofphere will be 108 times as high in pro- portion to his femi-diameter as ours is, and will rife [ 4oi ] to the diftance of more than ± of his femi-diameter from his furface. Let philofophers confider, whether thefe indica- tions of the vaft height of the fun’s atmofphere give any degree of probability to a conjecture of Sir Ifaac Newton’s, that the diflipation of the fun’s fubftance, which might be expeded to enfue from his intenfe heat, may in great part be prevented by the prodigious preffure of the incumbent atmo- fphere. The height of the atmofphere of Venus is con- fiderably greater according to the obfervations of Mayer and Rohlius than they imagined. Rohlius follows Caffini in the eftimation of the fun’s apogee femi-diameter, which Caffini over rated by 3" 45/,f/. This quantity, therefore, is to be added to the height of Venus’s atmofphere (15,5) as hated by Rohlius; which makes the true height i9//.2 5, that is above 4 of the diameter of the planet. I cannot but re- fled with fome degree of national triumph on the great part that our own country may juftly claim in many of the m oft curious difcoveries in all parts of the world. Mr. Meyer generoufly confefles how much he flood indebted to Englifli artifts. You told me that it is your intention to prefent that curious traCt to the Royal Society. You may likewife com- municate this if you think it contains any thing wor- thy of their notice. I am, Sir, with great efteem, Your moft obedient and moft humble fervant. Broad- Street, Tune n, 1767. vol. lvii. Sam. Horfley. XXXIX. Fff [ 402 ] XXXIX. Obfervations of the Sun s Eclipfe , 1 6 th of Auguftj 1765, taken at Caen m Normandy. ily Nathanael Pigott, Efquirey of Whitton, in Middlefex. Commimicated by J. Bevis, M. D. F. R . S. Read July 9, 1767 . Tr. Time. k / n At 3 57 28 the feg. of the fun’s ilium, diam. meaf. 4 8 52 the diftance of the horns ditto 4 18 39 the feg. of the illuminated diam. ditto 4 24 28 the diftance of the horns ditto 4 35 47 the °f the illuminated diam. ditto 4 43 4 the diftance of the horns ditto 4 52 38 the feg. of the illuminated diam. ditto 4 56 54 the diftance of the horns ditto r if ttr 29 38 H 14 47 37 27 4 35 16 20 24 27 H 14 14 26 6 29 52 1 7 46 4 h ill Sun’s inch diam. meaf. at 3 19 38 Ditto at 3 22 10 Sun’s horiz. diam. aft. 1 the Eclipfe J at 5 31 33 Sun’s inclined diam. 1 meaf. Auguft 15th] a 3 53 37 tt nt l1 ^ Iql the mean 31 42 58 [/ » '» 31 41 29 f 31 43 20 j of the Sun’s 31 43 42 I diam. meaf. Eclipfe t [ 403 ] // ir Eclipfe beg. tr. time at 3 48 16 end. at -5 o 56! * mid. at 4 24 36 dur. at 1 12 40I hence the mid. | 6 was at J J phafe whence the 1 eel. incr. for J 5 5/ of time in which the Sun’s diam. ilium, decreafed 36" 14"'} ihere- fore from the Sun’s diam. illuminated at 4 i3 39 = 27 4 35 take the decreafe in + 5 57— 0 3^ 14 the diam. of the Sun at the middle 4 24 36 = 26 28 21 which taken from the mean diam. meaf. 1 qi' 43" 20,/r gives J the quantity of the eclipfe, or fegment of the diameter eclipfed, which is 1 digit and 59', 15 of a digit, or 1 44 = 2 digits nearly. This eclipfe was obferved with an achromatic refradtor of 6 feet, and a micrometer made by Dollond. The weather very fine. The times, as computed from the Tables at the end of M. De la Lande’s Aftronomy. Beginning at 3 48 24*6 obferv. at 3 48 16 Middle 4 25 1 1,0 — ‘ 4 24 36 End 5 1 57>2 5 0 56’5 Duration i 13 32>6 1 12 4°>5 Alfo the latitude of the Moon was, by observation, 16" greater than the tables gave it. difference. t It o 8,6 0 35,0 1 0,7 o 52,1 F f f 2 XL. [ 4°+ ] HJS 2B ■XL. ExtraB of a Eetter from John Ellis, Ef quire, F. R. S. to Dr . Linmeus, of Upfal, F. R. S. on the Animal Nature of the Genus of Zoophytes , called Corallina . ^THAVE now finished a collection of 1/1 JL that genus of Zoophytes, which yon call Corallina j and, with the afliftance of our learned friend Dr. Solander, have made a defcription of each fpecies : to do this with more exadnefs, I have taken care to difiedt them minutely, and topafs them in re- view under his eye in the microscope, in order to eftablifh a true general character of this genus. I have attended more particularly to examine the nature of thefe bodies, in order to confute the opi- nions of fome late writers on Zoophytes, who, for want of good microfcopes, and a proper care in che- mically analyrtng them, have afferted that they, were mere vegetables. The firft of thefe is Dr. Job Barter, of Zeeland, who, in the Philofophical Tranfadtions, Vol. L1L p. ill, arterts that the Corallines of Linnasus, which he fays he has accurately examined, are inoft evidently true plants of the genus of Conferva ; becaufe there are no polypes coming out of their tops, and that they have feed inclofed in their cells like other ma- rine [ 4°5 3 rine plants *. But, as another part of this letter is intended for an inquiry into this new difeovery of Dr. Barter’s, that Corallines are Confervas; a thing never known even to the great Mr. Ray, Dr. Dil- lenius, or any other botanirt, I fhall now proceed , to his ingenious friend Dr.. Pallas of Berlin, who has lately redded in Holland, and who has taken great pains in collecting every thing that has been wrote on the fubjedt of Zoophytes, from whence he has compiled a book called Elenchus Zoophy- torum, where he has ranged the feveral genera and fpecies of this ciafs of beirtgs in a lyrteinatical order. When he comes to the. genus of Cor&llina, he fays (vide Pallas Elenchus, p. 418.) -(-, “ They are to frC be left to the botanirts, as they belong to the vegeta- “ ble kingdom ; but makes this apology for inferring “ them, leaft his book fhould be thought imperfedt, “ as Linnaeus and Ellis have ranked them as “ Zoophytes in their works.” * Oorallinas, non Zoophyta, quamvis Linnaeus iifdem adnu- meret, led veras e confervarum genere plantaseile, luculentiffime perfpexi. Nunquam in earum apicibus polypi inveniuntur: iemen contra cellulis inclufum eodem quo aliie plantae marinse modo produnt. Phil. Tranf. Vol. LII. p. 3. f Corallinas ad vegetabilia referendas elfe. Midi vero totum hocce genus botanicis relinquendum videtur. Nec enim ftrublu- ra, nec chymicis principiis ad Z'oophytorum ullum genus acce- dunt, et pleraeque fpecies etiam habitum prorfus peculiarem Iva- hent, aliquae ad fucos potius accedentes, plurimae confervis eomparahiles, quamvis lapidefcenti fubllantia ab iifdem et om- nibus vegetabilibus diftinbtiflirnae. Pallas Elenchus Zoophyt,. p. 418... He [ 4°6 ] He begins with obferving, that they don’t come near to any one genus of Zoophytes, neither in their ftru&ure nor chemical principles ; that fome fpecies have a peculiar appearance, fome approach to Fu- cus’s, many are like Confervas ; but that all of them are very diftinCt from them, and from all vegetables, on account of their lapidefeent fubftance. That they differ in their chemical principles from Zoophytes ; for when they are burnt, they fmell like vegetables : and that, according to Count Marfigli’s Experiments (Hift. Mar. p. 73.) they neither contain a volatile fait, or animal oil. That the pores, in their calcareous fubftance, are too fmall for polypes to inhabit them j and that the pores of Fucus’s prove them to be as much animals as the Corallines, even when their pores are rendered more vilible, by having the calcareous fubftance, that furrounds them, difl'olved by an acid. That the great Jufiieu, in his diligent refearches after marine productions could fee no vilible token of life in them. That Mr. Meefe, who has lately wrote a Flora Frifica, has found a Coralline growing upon a heath in Fried and ; which, Dr. Pallas fays, is a ftrong proof of their vegetable origin. Laftly, that their fructification is fo nearly ana- lagous to thofe of Fucufes and Confervas, that he likewife takes that to be a proof of their belonging to the vegetable kingdom. To proceed then. — Dr. Pallas, after telling us that Corallines are vegetables, fays, that fome of them are like Fucufes. In C 4°7 ] In this I muft agree with him ; becaafe his fir ft Coralline, which he calls Corallina Pavonia, is truly of that genus of plants: this mo ft elegant bucus I have particularly defcribed and figured (liffiy on. Corail. p. 88. T. 33. fig. c, d, e,)-, it is well known by the name of Turky- feather Fucus, and is called, in the Species Plant, p. 1630, Fucus Pavonius. What could have led Dr. Pallas into this miftake ? moft probably thofe beautiful farinaceous femi-circulai ftripes on it, which he muft have taken foi a lapi- defcent or calcareous fubftance ", one of the nroa diftinguifhing characters of a Coralline, even ac- cording to his own defcription of tnis genus. Il Ire had tried this farinaceous fubftance with an acid, he might obferve, that it would not ferment; it is of the fame nature with the farina that covers many plants, for inftance the Primula Auricula, and aimoft all the Lichenes foliacei and fruticulofi, or Liverworts. As to their fimilitude to the Conferva, tne conti ary will appear, as icon as I come to give the propei^ defini- tions to both thefe, and the Corallines. In tne faniu paragraph he fays, that the Corallines do not come near to any genus of Zoophytes. How far 'he is miftaken in this affertion, I will endeavour to prove from the following expeii- ments. Break a thin piece from the Corallium Anghcum, Efiay on Corall. T. 27. N. 1. c. (Millepora Calcarea, Pali as Elench. p. 265.) or of the Corallium Liche- noides, Eftay on Corall. T. 27. N. 2. d.\ both ^ Quamvis lapidifcenti fu'oftantia ab diftimStffimse. Pallas, Elench. 418. I omnibus vegetabilibus which j [ 4.08 3 which, Dr. Pallas, in his Elench. p. 265. has con- founded together under the name of Millepora Calcarea (but which he confefles to be animal) j and when you examine them in the microfcope, you will find in them both regular feries of cells, 3s figured in Eifay on Cor. Tab. 27. Fig. D. Split at the lame time one of the joints of the Coraliina Offici- nalis of Linnaeus lengthways, and you will find the leries of cells * correfpond in ffiape exadtly with both the former ; which I think proves the organization of thefe bodies to be the fame, and confequently animal. Befides thefe, compare the ftru<5ture of the Mi- riozoon of Donati, Phil. Tranf. Vol. XLVII. p. 107. Tab. 5. (Millepora truncata, Pallas Elench. p. 249.) with thole of the Coraliina Rofarium, and Coraliina incralfata, both which I have carefully dilfedled and figured in Tab. XVII. Fig. 15, 20, &c. and there appears fo great an affinity between their cells (and even in the opercula of the Coraliina incraffata), that it affords us.reafon to conclude with great probability, that their mouths, or fuckers, are the fame. It can- not be amils to mention the fimilitude there is be- tween the ftony-jointed Corallines, and the Ifis Hippuris, or jointed black and white Eaft Indian Coral, and the Cellularia balicornia, Pallas Zooph. p. 61. or Bugle Coralline, £ flay on Coral. T. 23. which two laft are univerfally allowed to be animals: in all thefe are found the fame kind of fibres that connect their joints, and exactly in the fame man- ner. In order to prove that thefe Corallines have a fmell very different from vegetables, I mu ft appeal to * See Tab. XVII. fig. 12 ami 13. [409] an experiment made publickly before the Society of Arts, Commerce, &c. and which gave them a fa- tisfadtory demonftration of the great difference in nature between Corallines and vegetable fubftances. It happened upon the following occalion. A gentle- man of Wales had fent the fociety a parcel of Lichen tartareus, of Linn. Ed. 2. Sp. Pi, 1608. as a propet material for dying a red colour, to anfwer the fame purpofe of that expenfive article among the dyers, called Orchell, or Canary weed, which is the Lichen Roccella of Linn. Sp. PI. 1622. As the objedt was of coniequence, the fociety was very defirous of being fully informed of the nature and appearance of this ufeful dye ; and therefore, feveral curious gentlemen of the fociety were de- fired, againft the next meeting, to bring fome fpe- cimens of true Orchell. Accordingly fome fpecimens were obtained from the Orchell dyeis in oouthwaik, and laid before the fociety. At the fame time Dr. Maningham, a member of that fociety, produced before the fociety a fpecimen, in a paper with Orchell wrote upon it, from Mr. Miller of Chelfea, likewife as the true Orchell: but, upon examining it, it proved to be the Coraluna neivo.te— nuori fragilionque internodia nedtente ot Sir x^.an;> Sloane’s Hiftory of Jamaica, Vol. I. Tab. 20. Fig. 4. Some difputes arifing on the. different appearance of the fpecimens, I took the liberty to inform the gen- tlemen prefent, that, having lately made fome expe- riments on Corallines, I believed that Mr. Miller’s fpecimen was a Coralline, or animal fubftance, and the Lichen Roccella, or Dyers Orchell, was a ve- getable ; and in order to convince the fociety of the / Vol.LVII. Cxgg difference. C 4*0 3 difference, I called for a lighted candle, and having firft fet fire -to the Lichen Roccella, it yielded the fame fmell that burnt vegetables ufually do ; but when the Coralline (which was Mr. Miller’s fpecimen) was burnt, it filled the room with fuch an offenfive fmell like that of burnt bones, or hair, that the door was obliged to be opened, to diffipate thedifagreeable fcent, and let in frefh air. Another argument that Dr. Pallas offers the world of the vegetable nature of Corallines, or rather a proof of their not being of an animal nature, are Count Marfigli’s Chemical experiments on the Corallina Officinalis (Hiff. Mar. p. 72.) where he fays it neither contains animal oil nor volatile falts. But, to prevent fuch plaufible arguments from tniffeading mankind, I determined to have fair and accurate experiments made on this fubffance. Ac- cordingly I applied to Mr. Peter Woulfe, F. R. S. a gentleman diffinguifhed for his great knowledge in chemiftry ; and in order to have the fpecimens frefh from the fea, I applied to a worthy member of this Society, the Right Honourable the Earl of Hillfbo- rough, for Mr. Potts, the Secretary to the Poff- Office, to procure me a fufficient quantity of the Corallina Officinalis from the fea-coaft near Har- wich : this parcel, about two months ago, I fent to Mr. Woulfe ; and in anfwer have received the fol- lowing letter, with an account of his experiments made on it. Clcrkenwcll, [ 411 ] Clerkenwell, May 5, 1767* S I R, IT O O K twelve ounces troy of the Corallina Officinalis .(which you fent me) picked clean from every extraneous fubftance, and put it into a clean ftone-coated retort ; the retort was fet in a reverbe- ratory furnace, and an adopter and quilled receiver luted to it : the fire was very gentle for the firft eight hours ; in which time, half an ounce and eighteen grains of a tranfparent and almoft colourlefs liquor came over, which was fet afide for examina- tion. The fire was then increafed, and in fix hours time there were diffilled two drams and three grains of a turbid liquor, which had fome appearance of oilinefs on its furface ; this was likewife fet a-partto be examined. The fire was then increafed for fix hours longer, and during the laft two hours the re- tort was quite red hot all over, which ended the- diffillation. In this third and laft procefs the portion of liquor that came over was more turbid than the fecond, and fome of it from the redundancy of its volatile alkaly was cryftallized ; it alfo contained ra- ther more than a dram of light empyreumatic oil., very much refembling the fmell of hartlhorn ; in the recipient there was alfo fome cryftals of a volatile alkali. The whole of this laft product weighed three drams and an half. The caput mortuurn was quite black, and weighed ten ounces, one dram, and-: one fcruple; fo that there was a lols of four drams and forty-nine grains out of the twelve ounces of Coralline. The C 4T2 ] The fir ft liquor that diftilled (lightly eftervefced with fpirit of fait, and changed fyrup of violets green, certain proofs of a volatile alkali. The iecond and third portion effervefced ftrongly with lpirit of fait, as did alfo the volatile fait that came over into the receiver, evident marks of its being a concentrated alkali. Here I muft obferve, that had this diftillation been condu&ed in a hurry, there would have been no concrete volatile alkali j for then this would have been confounded and diftolved in the firft liquor that came over. Had there been afufticient quantity of this Coral- line, I fhould firft have propofed to have taken off the calcareous fubftance, by an acid menftruum, and af- terwards wa(hed the membranaceous part fo clean from the acid, as not to change the fyrup of violets red. Then the diftillation of this part alone would have afforded a much larger proportion of empyreumatic oil, and volatile alkali, and but a very fmall quantity of caput mortuum. If you think thefe experiments of any ufe, you have my free leave to lay them before the Royal Society. I am, Sir, yours, &c. To John Ellis, Efq; in Grays Inn. Peter Woulfe. Doctor Pallas proceeds to prove that Corallines cannot be animals, as the * pores of their calcareous * Pori autem calcareae fubftantiae ita funt minuti, ut polypi in iis hofpitari nequeant. Pall.Eknch. p. 419. fubftances C 4-13 3 fubftances are too minute for any polypes to harbour in. Thefe words of the Doctor’s feem'to imply, as if the Coralline fubftances were only habitations for detached polypes, and not part of the animals them- felves. How this affair ftands, I hope to have cleariv demonftrated long before this, for I have plainly feen, and endeavoured to fliew mankind, that the fofter and harder parts of zoophytes are fo clofely connected with one another, that they cannot fepa- rateiy exift j and therefore have not hefitated to call them conftituent parts of the fame body, and that the polype-like fuckers are fo many mouths be- longing thereto. , . Now, for the fmallnefs of the pores, which the Dodtor has mentioned here (among the Corallines) to be a contradi&ion to animal life he certainly has forgot one circumftance, when he introduces the Corallium pumilum album (Effay Cor. T. 27./. c.) or his Millepora calcarea (Pall. Elench. P*2650 as an animal, which is, that he there fays, it has abfo- lutely no pores at allf. , As there can be no doubt, but every part of what is called Coralline is neceffary to make out fuch an animal, or being, it will be very difficult, if not almoft impoffible, to determine the propor- tion there ought to be between fofter and harder parts ; and therefore it cannot be thought un- reafonable to fay, that in fome of this tribe the ftony parts are by much the greater part of the whole, Specially as Dodtor Pallas’s objeaion can be only a gain ft the cruft, or lapidefcent part, as the m- fide of many of them is far from being hard, being f Pori omnino nulli. Pall. Elench. p. 266. exadtly [ 4*4 ] exadtly like a Sertularia, fo that I do not know if it would not be a good definition to one well acquainted with that tribe to fay, a Coralline is a Sertularia co- vered with a (tony or calcareous cruft ; if the mouths fhould happen to be very fmall, their number may make up that deficiency. We fee in the greateft number of Corallines their furface full of holes ; we law the fame in Efcharas and Milleporas thirty years ago ; fince that time magnifying glafles have been improved, fo as to fhew us, that they are all orifices, for polype-like fuckers; why fhould not we now admit that glafies may be ftill more improved, fo as even to make us able to fee what may be the intention and ufe of thefe minute orifices, which according to all rules of reafoning, we muft fuppofe to approach in nature to them they are moft alike. From this extreme minutenefs then of the pores of thefe Millepora, confelfed to be zoophytes, as well as thofe of Corallina officinalis as before mentioned, it is no great matter of furprize, that Dodfor Juffieu could not perceive any animal life in the Corallines, nor Dottor Schlofter in the Millepora calcarea. As thefe experiments ought to be attended with many convenient coinciding circumftances that do not often happen to perfons who only go to the lea- fide, perhaps for a few days, or hours, fo that it is unreafonable to conclude, becaufe they have been unfuccefsful, that more accurate obfervers may not be more fortunate at another time. I believe I fball be juftified in this, by many eliays . fnat haye been made, by perlbns of judgment, to obferve the’ polype-like fuckers in many, even of the Sertularia?, which they have feveral times attempted in 2 [415], in vain ; I mufl own it has often happened to me in many fpecies, and yet I have not the leaft doubt of their being true Sertularias from the fnnilarity there is in their habit and form to others of the fame genus; and of this fadt I am fure Dodtor Pallas is fully convinced. Another argument made ufe of by Dodtor Pallas, to overthrow the animal exiftence of Corallines, is taken from Mr. Meefe’s aflertion, that he had found on Bergummer Heath in Friefland, a fubftance of the fame nature with the Corallines. Meefe, in his Flora Frifica, p. 75. calls it a Lichen ; but Dodtor Pallas has ventured in his Elench. p. 427. to rank it among the Corallines, under the name of Corallina ter- reftris In this Dodtor Pallas is in the right, as I have had an opportunity of examining a fmall fpe-. cimen, that my worthy and learned friend Dodtor SchlofTer of Amfterdam was fo kind to procure me : but how fuch a nice and accurate philofopher as Dodtor Pallas could let it efcape him to conlider the nature and quality of this fubjedt, and how much it differs from any thing elfe growing on the land, is a thing that furprifes me* It only being mentioned by- Mr. Meefe, as found on Bergummer Heath, ought not to have fatisfied him fo far, as to declare a body with a calcareous cruft to be a land production, when no fuch thing in the whole vegetable kingdom has ever been found ; it has always been thought quite the contrary, that a ftony or hard fubftance of that na- ture, could not be produced, but from an animal, and chiefly thofe that live under water ■* See the figure of it in Tab. XVII. fig. 28. f ’Tis worthy of our notice how eafi’y this ingenious Natu- ral Hiftorian reconciles it to himfelf, that this inhabitant of tlve 1 This [ 4i6 ] This fhould certainly have made him minutely in- quire in what manner it was found, if buried under mofs, loofe on the ground, or perhaps near fome- of the canals, which communicate with the lea. Many accidents might have brought it thither, which is more probable than to imagine nature to go out of her ufual track. It is not improbable that that part of Holland has been overflowed by the fea, and this production lelt there when the water fubfided, or blown there by a ftorm, which I beg leave to believe till I am better informed. I do not in the leaft doubt of Mr. Meefe’s veracity ; but as that gentleman was more intent on difcovering vegetables than animals, and thinking this very like a dry Lichen fruticulofus, he did not fcruple to believe it to be one of that tribe j and therefore, perhaps, negleCted to obferve all thofe cir— cumftances, that we now wifh to be informed of. The irregular pedunculated figures or fructifica- tions (as DoCtor Pallas pleafes to call what is repre- fented in Tab. XVII. fig. 29.) teem to be rather a de- fect in the growth of the ramifications, efpecially as they differ from one another in fhape, and fome of them appear beginning to form other branches. In fig. a the whole confifts of two oppofite curled proceffes, with a fmall cavity between them at the top ; this cavity is filled up at fig. b. fo that the top becomes rounded j in fig. c. c. there feems to be a beginning of a continuation lengthways ; and in fig. d. it is ftill more plain the beginning of a branch. fea can grow on dry land. See Pallas Zoophyt. p. 427. -Nec magis miror Corallinam in ficco crefcentem, quain Lichejium cum Fucis fummam analogiam. ^ 3 C 417 1 If the infid e of thefe precedes had been hollow, and the cutfide of a regular figure, I fhould not have hefitated to confider them to be the ovaries of the Coralline; but as they ar-e folid, and of the fame firuFture with the red: of Corallines, I fiiail rather call them defective branches. DoCtor Pallas’s laft argument to prove that Coral- lines are vegetables is, that the nodules, or tubercles, which he has obferved in Corallines, contain little feeds fubanalogous, or fomewhat refembling thole we find in the fructification of the Fucus’s and Con- fervas. If this method- of reafoning fhould hold good, what will become of the Cellularias, Sertul arias, and Millepora calcarea & agaricifcrmis, with matny other zoophytes, that have fuch roundifh ovaries ; they muft be recalled to the vegetable kingdom, notwith- ffanding all doubt about their being living animals has long been laid a fide. I come now to his ingenious friend DoCtor Bafter, who carries this matter ftill farther, and fays poll- tiveiy , in Phil. Tranf. ,Vol. LII. p. 11 1. that the Corallines are true Confervas ; and in his Opufcula Subfeciva, Vol. I. Tab. I. fig. 3. A. and B. he re- fers us to the figure of the Corallina rubens in feed ; which, he fays, is a true Conferva ; but the figure is fo bad, that I am perfwaded nobody can find out what he means to reprelent by it. I fhall therefore conclude this letter, with re- commending to thefe ingenious gentlemen, to ana- lyfe thefe bodies chemically, and with care ; and likewife to view them with the fame attention, that I have done, in the microfcope ; if fo, I am Vol. LVII. Hhh per- C +l8 ] perfwaded they will be of our opinion. I muff de- fer the fequel of what I intended to another day, which was to give you an account of the difcoveries I have made in the fructification of the Confervas ; thefe, I flatter myfelf, will fully convince DoCtor Bafler of the great difference between thefe two bodies, and that they belong to two different king- doms of Nature. I am. S I R, * Your moft obedient Servant, John Ellis. Gray’s-Inn, June 2, 1767. tig- The Defcription of Plate XVH. 1. The Miriozoon of Donati, or Millepora truncata of Pallas. 2. The end of a branch magnified, to fhew the fituation of the pores. 3. The fame cut perpendicularly through, to fhew the Trumpet-like fuckers in their cells connected with the middle tubes. 4. The horizontal feCtion of the fame, with the fuckers extended. 5. Ihe magnified drawing of one of the fuckers, with its cell and operculum. 6. The i- - 1 ilt 1; • • ■! . Ji J ! ‘ . t >J j I rX' - jJU // JC UiUloiJ K • , :Ji ; .) . ' bn. «3tioq s/ij to bn& nrviifinj,- gru^ca iuoS’in .so irij r'giK, h sdtn >■ 6.' 7* 8. 9- 10. 1 1. 12. *3- 14. *5- 1*6. [ 4T9 ] The oblique view of the opening of the cell with the fucker and operculum. The cell with the operculum open. The cell covered with its operculum. The Coral lium Lichenoides of Ellis’s Corallines, with ovaries upon it. The natural and magnified fize of a piece of this Coral, to fhew the arrange- ment of the in fide of the cells, which are juft the fame as in the following. The order of the cells, in.a joint of the Corallina Officinalis, to fhew the great affinity between them. The natural fize of a fmall piece of the Corallina Officinalis. The milk-white Millepora calcarea, from the Mediterranean, where, though the pores are not vifible on the out- fide, the arrangement ot the cells^in the infide are the Erne with the Co- rallium Lichenoides, and Corallina Officinalis. The Corallina Rofarium, or White-bead band-ftring of Sloan s Hift. o*. Ja- maica, Tab. XX. fig. 3. Two joints magnified, one to (hew the fituation and figure of the pores, and the other to fhew how the fuckers pafs from the middle cartilaginous tube through the calcareous covering to the furface. H h h 2 1 7* Shews Fig. 17. [ 420 ] Shews four of the fuckers, and the ovary between them, magnified highly. 18. The Ovary. i 9. One of the eggs taken out of the ovary. 20. The Corallina incraflata, from the Weft- Indies. 21. One of the joints of its natural fize. 22. The lame magnified a little, to Ihew its pores in its calcareous furface. 23. Part of the infide tubes of the joint, of their natural fize. 24. The fame magnified, to Ihew the openings of the cells on the furface, con- nected together. 25. A perpendicular fedion of half of one of thefe joints. 26. The fame magnified, to Ihew the figure of the vefiels leading to the fuckers in the calcareous furface. 27. A piece of the calcareous furface highly magnified, to Ihew fome of the pores open, and others covered with their convex opercula j letter a Ihews the figure of one of the trumpet-fhaped fuckers highly magnified. 28. A fmall branch of Meefe’s Coralline fup- pofed to grow on a heath, called by Dr. Pallas Corallina terreftris. 29. The fame magnified, to fhew the difpo— fition and figures of its fuppofed frudification at a . b . c c. and d. which are higher magnified at A. B. C C. and D. to fhew how unlike they are to frudifications. S E- [ 421 ] S E Q_ U E L. Title read December 17, 1767. Read Jan. 14, T COME now to anfwer Do&or Bader, 17(08 • who aflerts pofitively, in his memoir publidied in the Tranfa&ions of the Royal Society* Vol. LII. p. hi, that all the Corallines, which you and I have defcribed, are plants of the genus of Conferva. In order to explain myfelf, it will be neceflary to let him know what I mean by a Conferva, and what I would be underdood by a Coralline, according to > your fydem. .... Bya Conferva I mean a plant with jointed filaments, either Angle or branched, bearing fruit, which are dilpofed in different ways: in Latin, thus, Conferva eft plant a, cm funt filamenta articulata , vel fimplicia vel ramofay jruElijicationes vario -modo difpofitce habentia. _ . . By a Coralline I mean an animal growing in tne form of a plant, whofe dem is dxed to other bodies. The dem is compofed of capillary tubes, whofe exr tremities, \ [422 ] trcmitles nafs through a calcareous cruft, and open into pores on the furface. The branches are often jointed, and always fub-divided into fmaller branches, which are either Joofe and unconnected, or joined, as if they were glued together : in Latin, thus. Cor alii na eft animal creftcens Kabitu planter. Stirps fixe^ e tubis c api liar ibus per cruft am c alca- ream poroftam ftcfte exerentibus compojita. Rami J'repe articulati , Jemper ramuloji , vel divari- cati liberi , vel co?ighitinati et conhcxi. This difference then will evidently appear by putting each kind into an acid liquor. The Coralline will immediately dilcover the nature of its * calca- reous furface, by a ftrong fermentation ; when the Conferva will not appear in the lqaft afteded. This acid liquor will likewife foon diffolve the calcareous fubflance in the Coralline, by which means the mi- nute velfels that lead to the pores on the furface will become vifible ; whereas the Conferva will unal- terably remain the fame, and be rather preferred than corroded by the acid. When Dodor Pallas, who fupports the opinion of Dodor Balder, comes to the chemical analyfis of the Corallines, he tells us ft that he had not time nor opportunity to try them ; but depends on the report of other authors. * Lin. Syft. Nat. Ed. 12. p. 1304. “ Corallinas ad reg- “ num animale pertinere ex fubftantia earum calcarea conftat, “ cum omhem -calcfem animalium elTe piodu&um veriflimum “ fit.” f Fallas Zooph. p. 418. “ Temporis anguftia et oppor- tunitas impediverit ne in Corallinaium riaturam accutatius “ igne inquirerem.” This [ 423 ] This dependence on the authority of others, to overturn what I think we have eftablifhed with very rtrong evidence, will, I am in hopes, convince him of the propriety of that welhchofen motto of the Royal Society. “ Nullius in verba ; which I find he has adopted as the common feal of his epifties to his literary correfpondents : and he will now have a further opportunity of * complimenting Do&or Barter on making a fecond apology for what he has advanced againft me in the fhil. Tianf Vo). LII. p. in. by (hewing him, that they have both been miftaken in blending two very different geneia of the animal and vegetable kingdoms of nature to- gether. To make this difference appear ftill more evident, I come now to lay before you a new fcene ot n.ttuiej which an accurate examination into the gratifica- tion, as well as the articulations, of fome 01 the Con- fervas, afforded me. Indeed the minutenefs of thefe objects would fcarce feem worth while to examine into fo critically, if my reputation had not engaged me to fliew the wide difference between them and Corallines. This, joined to fome remarkable difco- veries, which I made in the year ^754 on coa^L of Suffex (in company with Mr. G. D. Ehret, F.R. S.) in the fructification ot this clafs of plants, which * Pallas Zooph. p. 20. “ Candidifllmus Bafterus, qui hue- “ ufque Contra Ellifium reliquofque prioris fententise patronos *t fteterat, alterius evidential vi£tas dedit manus, et gloriofnLmo exemplo, repudiata priori fua opin’tone, veram theoriam acri- “ ter def'endere ccepit,” , * before.. [ 424 ] before that time were cftrethed by * botanical writers to have no fructification at ail, lias induced me to lay a few fpccimens of them with their mag- mfied drawings' before the Royal Society. 6 In examining thcfe plants I was amazed to find two fpecies of them evidently of your clafs of Dioecia ; that is, male parts of fructification on one and female on the other. 1 he. firld of thefe is the Conferva polymorpha, where in I ah. X VIII. at fig. a . is reprefented a very fimal 1 branch of the female in its natural fize, and at fig* A. the fame is magnified: in tlic tranfparent capfules of this fpecimen, we can eafily difeover the i>-cd .is it lies expanded in a watcn-glals in water. Lettci b. reprefents the natural lize of a lmall branch of the male. Letter B. the fame branch magnified, fliewing its amentaceous flowers, or catkins, with its minute male feed in fpikes. B i. fliews one of them highly magnified. The other Conferva is the Piumofa, and is one of our mofl elegant fub-marine plants. Fig. c. repre- fents the natural fize of a minute fprig of the fe- male. At fig. C. the lame is magnified, where the feeds appear in their capfules. the fig. d. fliews the natural fize of a fprig of the male Conferva piumofa ; and fig. D. the fame fprig magnified, fliew- ing the fpikes of male feed. * Ray, Synop. Ed. 3. p. 57. “ Conferva eft Mufci genus cc fterile et capitulis floridis deftitutum, immo nec peltis & tu- “ berculis, quae horum loco aliqui gerunt, donatum, ex meris “ fbliis teretibus et uniformibus feu mavis cauliculis, in tenuia “ capillamenta divifis, conftans.” JL The [ 425 ] The next is the Conferva flofculofa, and is repre- fented at fig, e. in a branch of the natural fize. big. E. is the fame magnified. This is one of thole re- markable Confervas that has footftalks to its .flowers or fr unification. It appears to have fruit like a ftraw- berry, or rafpberry, furrounded by a leafy calyx. This was found on the fea-coafi, near Yarmouth in Norfolk, by my worthy friend George Whatley, Efquire, in the year 1764. When it was frefh, it was of a moft vivid carmine colour. The other with flowers, at fig./, is the Conferva geniculate. Fig. F. fhews the fame branch more diftindtly, being magnified with flowers furrounding the joints ; this, with one which I have called in my catalogue of Confervas, Conferva florifera, I difeovered in the year 1754 near Brighthelmftone in Suflex, when Mr. Ehret was fo kind as to make drawings of them while recent. The colour of this, when frefh, is a fine fcarlet. The Conferva plumula, at fig. g. is one of the fmalleft of the tribe, but moft' elegantly feathered ; it is of a pale red colour. The fame is magnified at fig. G. which fhews the order that the fruit and branches are difpofed in. G 1 fhews the fruit or feeds, which are of a red colour, furrounded by a clear gelatinous pulp. The Conferva at fig. h. I have called Ciliata, from the circle of fmall fibres at the top of each joint. The magnified drawing at fig. H. fhews thefe fibres like a crown on each joint. This was inferted here to fhew, with the reft, fome of the infinite variety of beautiful forms, which the great Author of nature has imprefled even upon one of the loweft dalles of the vegetable tribe. Vol. LVII. lii Before [ 426 ] Before I conclude, I mud: obeferve; That as Do&or Pallas has likewile introduced among his arguments, that the fruit of the Fucus’s are fubanalogous to thofe of the Corallines, I could introduce an infinite variety to Ihew the great dif- ference there is between them ; but this part of natural hi (lory, too long neglected, requires a vo- lume by itfelf, to fhe^w the amazing variety of vege- tables, that lie hid from us in the great deep ; I may make fome obfervaticns on them the fubjedt of a future letter, efpecially as many, of them are of the clafs of Dioecia, as well as thofe which I have al- ready (hewn in the Confervas ; which I believe will be new to the botanids. I am, Dear Sir, Your mod obedient fervant, John Ellis. The Defcription of Plate XVIII. Fig. a A. b. B. B i. The female Conferva polymcrpha. The fame magnified, to £hew the feeds in the Capfules. The male Conferva polymorpha. The fame magnified, with its male flowers. One of the catkins, or male flowers, highly magnified. The female Conferva plumofa. The rhilTrans:YolLVlLTab.3Vin;/p.42^ Tjd ■ 1 / c. [ 427 ] The fame magnified, to fhew its fr uni- fication. d. The male Conferva plumofa. D. The fame magnified, fhewing its catkins, or male flowers. e. Conferva flofculofa. E. The lame magnified, fhewing its pedun- culated flowers, or fruit, with their polypetalous cups. f Conferva geniculata. F. The fame magnified, to fhew its flowers furrounding the joints. g. Conferva plumula. G. Part of it magnified, to fhew the dilpo- fition of its branches. G 1. Some of the fruit highly magnified, to fhew its feeds, furrounded by a clear vifcid pulp. h. Conferva ciliata. H. The fame magnified, to fhew the little coronets on the joints. I i i 2 XLI. An C 4-28 ] XL I. An Account of the ASlinia Sociata , or Clujlered Animal-flower , lately found on the Sea-Coafls of the new-ceded IJlands : In a Letter from John Ellis, Ef quire , F. R. S. to the Right Honourable the Earl of Elillfborough, F. R. S. My Lord, Read Nov. i2, MONG the many curious ma- _/ \ rine animals, which your Lord- Chip has received from the new-ceded iflands in the Weft-Indies, there is one moft uncommonly rare : this is of great confequence to natural hiftory, as it feems to bring together two remarkable genera in the fyftem of nature, which Profeffor Linnaeus had removed far from each other. The one is the Adtinia or Animal flower, the other the Hydra or Frefh-water polype. The Adtinia, called by old authors, as Aldrovan- dus, Johnfton, &c. Urtica marina, from its fuppofed property of flinging, is now more properly called by fome late Englifh authors the Animal flower. This name feems well adapted to it ; for the claws, or tentacles, being difpofed in regular circles, and tinged with a variety of bright lively colours, very nearly reprefent the beautiful petals of fome of our moft elegantly fringed and radiated flowers, fuch as the Carnation, Marygold, and Anemone. As there are C 429 ] are great variety of fpecies of this animal, fo thefe fpecies differ from each other in their form. The bodies of lome of them are hemifpherical, others cy- lindrical, and others (h aped like a fig. Their fub- ftance likewife differs ; for fome are "(tiff and gela- tinous, others flefihy and rrmfcular ; but they are all capable of altering their fhape, when they extend their bodies and claws in fearch of their food. We find them on our rocky coafts at low water, fixed in the (hallows to fome folid fubdance, by a broad bafe like a fucker; but they can fhift their fit ifation, though their movement is very flow. They have only one opening, which is in the center of the uppermoft part of the animal ; round this aie placed rows of flefliy claws ; this opening is the mouth of the animal, and is capable of great extenfion : it is amazing to fee what large (hell fi(h fome of them can fwallow, fuch as mufcles, crabs, &c. when it has fucked out the fifli, it throws back the (hells through the fame paffage. Through this opening it likewife produces its young ones alive, already furniflied with little claws ; which, as foon as they fix tnemfelves, they begin to extend in fearch of food. They are found all round the coafis of England ; but the coafts of Suliex and Cornwall furnifh us with the greateft varieties of them. The ifiands in the Wed Indies are likewife remarkable for many kinds of them, as appear from the different forts fent to your Lordfhip by Mr. Greg. Do&or Gaertner, F. R. S. who has deferibed four fpecies of the Englifh ones in. the Phil. Trank * fays * Vide Phil. Tranf. Vol. LJL p. 75. Tab. I. fig. 1, 2, 4, and 5 ; the animal in fig. 3, in the lame Plate is ranked in I they [ 43° 1 they have the remarkable property of renewing their claws when they are cut off ; and ranks them, per- haps very properly, under the genus of Hydra of Linnaeus, or Freth-water polype: which I fhali now give a fhort defeription cf, that we may judge how near your Lordfhip’s new animal approaches to both of thefe. The Hydra, or Frefh- water polype, is that extra- ordinary animal lo well known to the curious, from the diicoveries of Mr. Abraham Trembley, F. R. S. in its re-produdtion after it had been cut into pieces. When it is extended, it is of a worm-fhaped figure, and of the fame tender fubftance with the horns of a common lhail. It adheres by one end like a fucker to water plants and other fubffances : the other end, which is the head, is lurrounded by many arms or feelers placed like rays round a center: this center is its mouth, and with thefe arms, which are capable of great exten- sion, it feizes fmall worms and water in lefts, and brings them to its mouth ; often fwallowing bodies larger than itfelf : when the food is digefted in the ftomach, it returns the remains of the animals it feeds on, through its mouth again, having no other vifible patfage from its body. Their manner of multiplying is from eggs, which they produce in autumn*; but the moft common is from their fides, in which there firft appear fmall Lnobs, or papillae; as thefe increafe in length, little .this genus by Doftor Pallas, as well as Doftor Gaertner, but very improperly, as it has many feet, and a paflage through its 'body. Doftor Linnreus calls it Holothuria. * See Pallas, Zoophyt. p. ah’, 2 fibres [ 431 ] fibres are feen rifing out of the circumference of their heads, which they foon ufe to procure food. When they are thus arrived at a mature Hate, they fend forth other young ones from their fides : fo that though many of them foon fall oft, and provide for themfelves, yet the animal frequently branches out into a numerous offspring, growing out of one com- mon parent, each of which not only procures nou- rifhment for itfelf, but for the whole family. I come now to your Lordfhip’s new animal ; and, for the Satisfadion of the Royal Society, lay before them one of your Lordfhip’s fpecimens preferved in fpirits,. with a diffedion of one of them, to fhew its internal ftrudure, together with three fpecies of Adinia, or Animal flowers, fent to your Lordfhip from the new* ceded iflands. This compound animal, which is of a tender flefhy fubftance, confifts of many tubular bodies, fwelling gently towards the upper part, and ending like a bulb, or very finall onion ; on the top of each is its mouth, furrounded by one or two rows of tentacles, or claws, which when con traded look like circles of beads. The lower part of all thefe bodies have a com- munication with a firm flefhy wrinkled tube, which flicks faft to the rocks, and fends forth other flefhy tubes, which creep along them in various diredions-. Thefe. are full of different fizes of thefe remarkable animals, which rife up irregularly in groupes near to one another. This adhering tube, that fecures them faft to the rock, or flielly bottom, is worthy of our notice. The knobs that we obferve,. are formed in feve'ral parts [ 43 2 ] parts of it, by its infinuating itfelf into the inequa- lities of the coral rock, or by grafting pieces of fhells, part of which dill remain in it, with the flefhy fub dance grown over them. This {hews us the indlnd of nature, that direds thefe animals to preferve themfelves from the vio- lence of the waves, not unlike the anchoring of mufcles, by their fine filken filaments, that end in fuckers j or rather like the fheily bales of the Ser- pula, or Worm-diell, theTree Oyder, and the Slipper Barnicle, dec. whofe bales conform to the diape of whatever fubdance they fix themfelves to, grafpingit fall with their tedaceous claws, to withdand the fury of a dorm. When we view the infidc of this animal difleded lengthways, we find a little tube like a gullet leading from the mouth to the domach, from whence there rife eight wrinkled fmall guts, in a circular order, with a yellowilh foft l'ubftance in them; thefe bend over in the form of arches towards the lower part of the bulb, from whence they may be traced down- wards, to the narrow part of the upright tube, till they come to the flefhy adhering tube, where fome of them may be perceived entering into a papilla, or the beginning of an animal of the like kind, mod probably to convey it nourilhment, till it is provided with claws : the remaining part of thele flender guts are continued on in the flefhy tube, without doubt for the fame purpofe of producing and fup- porting more young ones from the fame common parent. The many longitudinal fibres, that we difeover lying parallel to each other, on the infide of the l'emi- [ 433 ] femi-tranfparent fkin, are all inferted in the feveral claws round the animal’s mouth, and are plainly the tendons of the mufcles, for moving and directing the claws, at the will of the animal ; thefe may be likewife traced down to the adhering tube. As this fpecimen has been preferved in fpirits, the colour of the animal when living cannot certainly be known ; it is at prefent of a pale yellowifh brown. With regard to its name, it may be called Adtinia fociata, or the Clufter animal flower. Among the critics, my Lord, I am aware of this ; that it may be faid, that an animal compounded of many animals has not a very philofophical found. But it is well known to thofe, who underfland the nature of zoophytes ; that there are many kinds of thefe animals, as well fuch as fwim about freely, as fuch as are fixt to rocks and fliells in the fea, that have a great many mouths in the form of polypes, and yet are but Angle animals ; fuch as the great va- riety of Pennatulas, or Sea pens, among thofe that fwim about, and moil of the Sertularias, Gorgonias, with many others, among thofe that are fixt. Yet this new animal of your Lordfhip’s differs very much from the generality of thefe. I think I may compare it, to fpeak in the flyle of thofe who main- tain that zoophytes vegetate, to a timber tree, that fends out at a diftance round it many fuckers from its roots, which fuckers coming in time to be trees, thefe may and will, with propriety, be reckoned fo many diltindt trees, though connected at their roots with the parent tree, and that without any abfur- dity. > Vol. LVII. K k k Left [ 434 ] Left any doubt fhould (till arife in this abftrufc part of the operations of nature, it may be proper that I lhould explain myfelf further, by fhewing that there are a great many zoophytes, which were formerly called Corallines, now Sertularias and Cellu- larias, that from a creeping adhering tube fend up feveral tingle animals, others fend up feveral branched animals. To give an inftance or two of each, I fhall mention the Sertularia uniflora, or Single bell- Ihaped Coralline (fee the Eflay on Corallines, PI. XIV. fig. A and B) and the Cellularia anguina, or Snake’s head coralline (fee the fame Eflay, PI. XXII. fig. C) both which, like our A&inia fociata, fend up diftindt animals with one mouth each. Whereas the Sertularia pumila, or Sea oak coral- line (fee Eflay on Coralline, PI. V. fig. A) and the Cellularia burfaria, or Shepherd purle coralline (fee the fame Eflay, PI. XX. fig. A) fend out ani- mals, in the form of fpikes or branches, that have many mouths from their own creeping and adhering tubes j and yet both thofe with one mouth to each, and thefe with many, I efteem as fo many diftindt animals, notwithftanding their being connected by an adhering tube, as I have faid in the inftance of the tree and its fuckers. To conclude, my Lord, the importance of the difcovery of this new animal to natural hiftory is this, that it clears up that much-difputed point, which is, that the extenlion or increafe of the fubftance of thefe zoophytes is of an animal, and not of a vegetable growth (as fome late authors would have us think) by thus making the fadt more clear and evident to our fenfes. 7 For C 43 S 3 Eor the poetical defcriptions of fome late fyftema* tical authors have tended rather to confufe than ex- plain thefe matters to our ideas ; for inftance, they call thefe bodies, that rife up like a fpike with many mouths, a vegetating ftem, and their mouths, which are formed like fo many polypes, flowers ; though with thefe fuppofed flowers, they evidently feize their food, by ftretching out their claws (which they call the petals) to convey it to their mouths, that are in the center of each, to fwaliow it, digeft it, and re- turn the non-nutritive parts back again by the fame way. Can this then be called a vegetative life ? But happily this animal of your Lordfhip’s is large enough for difledtion ; and in that hate difco- vers to us, not only mufcles and tendons, but a fto- mach to digeft, and inteftines to fecrete, proper nou- rifhment for the fupport and increafe of itfelf and its progeny ; which I am perfwaded is the ftrongeft proof that has yet appeared to convince the learned world, that zoophytes are true animals, and in no part vegetable ; and that the Royal Society are highly obliged to your Lordfhip for this moft valuable ac- quifition in natural hiftory, as well as he who has the honour to be, My Lord, Your Lordfhip’s moft devoted, and much obliged humble fervant Gray’s-Inn, Aug. 1 7, 1767, K kk 2 Th« John Ellis. [ 43& ] The Defcription of Plate XIX. The ACtinia fociata, or Cluftered animal flower, with its radical tube adhering to a rock, (tf) One of the animals flretching out its claws. A perpendicular diile&ion of one of thefe bodies, to fhew the gullet, inteftines, ftomacb, and fibres, or tendons, that move the claws. (#) A young one ariflng out of the adhering tube. 1 he ACtinia after, or Sea ftar flower, from the new ceded Iflands. The A&inia anemone, or Sea anemone, from the fame place. The under part of the fame, by which it adheres to rocks. I he Actinia helianthus, or Sea fun-flower, from the fame place. The under part of the fame. The Acftinia dianthus, or Sea carnation, from the rocks at Haftings in Suflex : this animal adheres by its tail, or fucker, to the under part of the pro- jecting rocks, oppofite to the town ; and, when the tide is out, has the appear- ance of a long white fig : this is the form of it when it is put into a glafs of fea-water. It is introduced here as a new variety of this animal, not yet deferibed. 9. The I m ] ■ niJBioo b&qj ' ( £ ■ \ H } V. V. . % JUX Fig. 9. C 4-37 3 The Sertularia uniflora, or Single bell- Ihaped coralline magnified. ( a ) One of its ovaries. 10. The Cellularia anguina, or Snake’s-head coralline, magnified. 1 1. The Sertularia pumila, or Sea-oak coral- line, magnified. (*z) One of its ova- ries. 12. The Cellularia burfaria, or Shepherd’s purfe coralline, magnified. XL1L A [ 43& I I ( { < y Received October io, 1767, "i XLII. A Letter from Edward Wortley Montagu, Efquirey F. R. S . to William Watfon, M. D. F. R. S. containing fome new Obfervations on what is ^//^Pompey’s Pillar, in Egypt. SIR, ftead Nov. 19, T" HERE fend you a few lines, which 1?67* J[ I believe will appear extraordinary, as every traveller that has been at Alexandria has mentioned the famous pillar of Oriental Granite, which is about a mile without the walls of that city, as eredfed, either by Pompey, or to the honour of Pompey. As I differ in opinion from them all, and think this famous pillar was eredted to the honour of Vefpafian, you certainly will expedt to hear on what foundation I found fo extraordina- ry a conjedture, as fo new a one may appear to you. By C 439 ] By my menf. the capital of the pillar is The Shaft > ■— » The Bafe . The Pedeftal — . Height from the Ground — — — Its Diameter — - F. In. 9 7 66 i 5 9 IO 5 8 £<3 4- CS * 92 O 9 1 As foon as I faw this fill-prizing pillar, I was con- vinced that, if it had been eretfted in Pompey’s time, Strabo, or fome of the ancients, would have men- tioned it : I therefore determined to examine it nar- rowly. I perceived too that the pedeftal was of a bad and weak mafonry, compofed of fmall and great ftones of different forts, and abfolutely unable to fuftain fo great a weight ; 1 therefore eaftly con- cluded fuch pedeftal not originally belonging to the pillar. I attempted to get out a ftone, which I did without trouble, and difcovcred the pedeftal to be hollow. After fome time, I mean during the courle of many days, I made an opening wide enough to enter it ; when within it, you will judge how much I was furprized to find this prodigious mafs of gra- nite, flood, as on a pivot, on a reverfed obelifk, as I then believed it was, only five feet fquare; curious to know the length of the obelifk, I began to move the earth on one of its fides, but my furprize in- creafed much when I found, after moving a few inches of the foil, that the obelifk was not entire, this pivot being only four feet and one inch thick. It is l'eated on a rock ; the ftone is of an extreme hard- nels, [ 44° ] nefs, and almoft a petrification or rather conglutination of many different ftones, but all vitrefcent. I never met with any ftone of this kind any where, except with one fmall piece on the plain of the Mommies ; I broke a piece of it, which Lord Bute has ; a fmall piece too of the pillar was fent, that gentlemen may be convinced it is of red granite, and not a compo- fition as fome have imagined. This part of obelifk is covered with hieroglyphicks, which are reverfed, a plain proof the pillar was not ere&ed whilft they were held facred characters. Convinced, therefore, that it was not of the an- tiquity one would fuppofe it, from being called of Pompey, I vifited it feveral times to fee if it might not be poifible to find out fomething that would give room for a reafonable conjecture, in honour of whom, or at what time, it was ereCted. From the infcription I could difcover nothing ; it is on the weft face of the bale, but fo much injured by time, and I may fay too by malice, for the mark of an inftrument are plainly difcnvered effacing it, that one can but imperfectly make out fome Greek cha- racters, fo imperfectly indeed that no one word can be found. At length, obferving that the cement, or mortar, which clofes the fmall feparation of the fhaft from the bafe, was quite deftroyed in one part, I was cu- rious to fee if any thing was made ufe of within, to fallen or tie the fhaft to the bafe ; I faw there was : being defirous to know if it was lead, and if fo, if it was not of that pure, and of which we ftill meet with fome few medals ; I endeavoured with a pretty large hanger to 'cut off a fmall piece of the grapple s [ 441 3 grapple ; there was a great number of lizards which had taken fhelter there, and which run out on my introducing the hanger. I then difcovered a dark fpot, at the diftance of more than a foot, within the circumference of the pillar; which, bv ftriking it with the hanger, I found wasfomething (luck faft to the bafe ; after ftriking it feveral times, I detached it from its place, and it proved a medal of Vefpa- ftan in fine order. AVT. KAI2. SEBA. OVEEfl.... The reverfe is, Victoria gradient ; Dextra Jiicas , finif. pabnam . This medal was fiewn to the Royal Society . The reverfed hieroglyphicks are a proof that this amazing monument was not eredted before Pompey’s time ; and as there is no mention of it in Strabo, or any one of the antient writers that I have met with., it feems plain it was not known before the time of Vefpafian. This medal could not by any accident, I think, have been introduced above a foot within the circumference of the (haft ; therefore I fuppofe it was placed there when the pillar was eredted, which from thence I conclude to have been done to the honour of that emperor; and perhaps on his reftoring the cripple to the ufe of his limbs.. If you think this paper worth it, you will pleafe to communicate it to the Royal Society, and that of the Antiquaries. The pillar is ex&dtly ihewn, with the pivot it ftands upon, with a reference to the fpot the medal was found upon, in the view of it that I have fent to England. Vol. LVII. Lll I beg [ 442 ] I beg you will allure the Society of my refpe but was not examined before or after the Sun fet$ fo that the lowefl State cf the 1 hermometer in thefe Parts is not afeertained. J A N U A R Y 1767. Day 3 4 5 6 7 8 9 10 9 1 1 9 1 1 9 1 1 9 1 1 9 1 1 9 1 1 9 1 1 9 1 1 9 1 1 <2 1 1 a. P- a. P- a. P* a. P- a. P* a. P- a. P- a. P- a. P* a. P- m. in. m rn. m. in. in. in. m. m. in. m. m. m in. m. m m. m. m. Bar. 30 20 29 84 29 82 29 65 29 6b 29 77 29 88 29 96 9 95 29 91 29 75 29 74 29 64 29 56 29 61 29 70 2 9 70 29 72 29 60 29 46 Ther. jThci within with doors. 44 45 42 40 40 39 3S 35 33 35 35 38 39 39 36 35 35 35 34 34 out doors. 32 30 30 33 23 Wind. N'. E. b. N. NT. E. N. E. N. N. E. N. E. E. E. N. E. N. W. N. N. W. N. W. E. b. N. S. W. E. b. N. N. E. N. N. W. N. W. s. w. 2 3 2' 2 2' 2 2 2 2 2 0 1 2 2 1 2 2 Rain Weather. Clear D° a remark, gull of wind for fome h. in the n. Clear D° with froft this night and the laft Fair ; a few flakes of fnow fell thro’ the day Clear D° a very fbarp air D° D° D° D° Cloudy ; little or no frofl: [Hazy .230 Rain, heavy ; but towards morn, fevere froft Froft ; clear with a very (harp air Heavy falls of fnow Slight falls of fnow at times Clear and {harp air * Cloudy ; and towards morning rain 11. y 9 ii 9 1 1 9 i 1 1 9 hi 9 hi 9 II I 9 ii i 9 hi 9 1 1 9 1 1 a. P- a. P- a. P- a. P- a. P- a. P- a. P- a. P* a. P- a. P- m. m. m m. m m. m. m. m. m. m. m. m. m. m. m. m. m. m. m. Bar. 29 22 29 20 29 1 7 29 15 28 92 28 67 28 67 28 90 29 30 29 36 29 42 29 55 9 70 29 80 29 82 29 90 29 90 29 92 30 o 30 8 Ther. jTher. within with- doors. 33 33 32 35 37 39 40 42 44 45 44 4+ 40 44 36 35 35 38 36 out doors. t 447 3 Wind 24 24 27 3s |34 N. N. N. W. S. W. S. S. E. S. E. S. 8. S. S. E. S. S. E. S. S. E. E. N. E. E. b. N. N. E. NT. E. N. N. W. N. N. W. 1 1 1 2 2" 3 2 2 2" 2 "■ 2" 2 2 2 2 2 1 o o Rain .110 .960 -32° Weather .070 Hail; fleet ; and after, moft heavy fall of fnow Cloudy; fnow in 3 h. cov. upw. 6 inch, deep Clear wind with the fun ; a very fine day Cloudy. N. B. Thermometer at noon 24 Cloudy ; fnow every where melt, by the thaw Rain heavy through the night ; ftormy Heavy rain in the mom. fhovvery thro’ tiie day Showery Cloudy, with fun-fhine at times Cloudy Showery Cloudy Cloudy ; with a fiiarp cold air D° Fair; air very fiiarp Clear and froft Clear til] 4 p. m. then (how cry Clear and froft D° Cloudy ; thaw ; towards morning rain [ 4+3 ] Depth of Rain which has fallen at Plymouth during the Year 1766. Dec. 1^-66 Inc. Parts Barom. hig. Hate Barom. low. Hate January 0 .165 3° 74 29 83 February 2 .590 3° 65 29 40 28 83 March 1 -690 3° 45 April 3 780 3° 43 29 2O May 2 .600 3° 23 29 2 1 June 3 .880 30 21 29 33 July 3 -55° 3° 3 29 56 Auguft 1 .boo 3° 10 29 44 September 2 .630 30 20 29 45 29 08 October 2 .650 3° 45 November 4 .660 3° 5° 28 62 December 3 .280 Inches 35 .075 30 44 29 14 N. B. In the latter end of December 1766, the weather was fo mild, and had been to in the pre- ceding weeks, that ripe ftrawberries were gathered in my garden at the Royal Hofpital, Meteorogical [ 4-49 ] 1 fceorological Regifter, kept at the Royal Hofpital near Plymouth, continued from January 20, to March 1, 1767. 1 I ! Bar. Thr. Wind Rain 9 a. m. 29 97 39 W. b. S. 2 ii 1 P- m. 29 92 40 W. b. S, 1 9 a. m. 29 67 42 W. b. S. 2" 11 1 P- m. 29 74 44 N. W. 2 9 a. m. 29 94 44 N. 2 1 1 P- m. 29 c 45 N. 2 9 a. m. 29 90 46 S. W. 2 111 P- m. 29 8x 48 s. w. 2' .310 9 a. m. 29 72 49 s. w. 2!" 11 1 P- m. 29 65 49 s. w. 2'" 9 a. m. 29 62 49 s. w. 2"' . 148 111 P- m. 29 68 49 W, b, S. 2 9 a. m. 29 5° 50 s. 3 hi P‘ m. 29 5* 50 S. S. E. 2" 9 a. m. 29 67 50 N. N. E. 2 .960 11 1 P- m. 29 5° 49-5 N. E. 1 9 a. m. 29 77 46 S. S. E. 2 •572 11 1 P- m. 29 77 48 S'. S. E. 2 9 a. m. 29 73 50 S, W. 2 11 1 P- m. 29 72 51 S. W. 2 •53° 9 a. m. 29 73 52 S. S. W. 2 ri 1 P* m. 29 78 53 S. 2 420 9 a. m. 29 90 52 S. S. E. 1 11 1 P- m. 29 74 53 S. S. W. 2 9 a. m. 29 °9 52 5. E. 1 11 1 P- m. 29 91 53 3. E. 1 4240 9 a. m. 29 83 51 S.‘E. 2 11 1 P- m. 29 72 52 E. 1 9 a. m. 29 60 pi E. 0 ii 1 P- m. 29 56 49 E. b. S. 2 9 a. m. 29 54 5i E. 2 ii 1 P- IT). 29 59 i5° E. 2' 9 a. m. 29 60 48 E. b* S. 2 1 1 P- m. 29 41 51 E. 2" 9 a. m. 29 2.1 5i E. 2 •340 1 1 P m 29 i5 5i 3. 2 M i/OL. LV1I . Weather Remarks Slight fhowers Cloudy Small rain conftant thro’ the day Cloudy Showery, but clear for the moft part Cloudy weather Small rain through the day D° Cloudy, with fmall rain at times D° Showers in the forenoon, afterw. clear' ?°Udy ' , n , , , of Therm. $ » Rain heavy and conftant thro the day j D° Small rain through the day Rain Rain from noon till 4 p. m» Cloudy Fair till 1 1 a. m. Rain conftant fince n a. m. Rain conftant, with hazy weather Small rain Higheft flat e 7 of Barom. 5 ^ Loweft ftate ? of Barom. ^ “9 ^ Higheft ftatc 7 of Therm. 5 ^ Fog, with fmall n aft. heavy thro’ day Cloudy * Hazy weather, with rain at times D° ■ Fair, with fun-fhine thro’ the day Clear Fair through the day Clear D° Cloudy Small rain, with hazy weather Rain Hazy, with fhowers Heavy (bowers, with fqualls. The quantity of rain is very confiderable during this period ; land yet, on looking back into the re- [gifter, I find that in the month of March l7 65> Inc. the total is 1 0.820 and taking in from the 23d of February, to the 2d of April 1765, viz. 39 daysj Inc. theamount? is ^ I3,S0° A quantity equal, I fuppofe, to what ufually falls in fix months, in moft parts of England, being neatly fourteeA inches. Day i Day Feb. Bar. Th'. Wind 8 9 a. m. 29 51 s. w. 2" 1 1 p* m.1 29 1 3 50.5 S. W. 2 9 9 a. m. 29 32 51 E. I 1 1 p. m. 29 37 5i s. w. 2 10 9 a. m. 29 n'si s. w. 2" 1 1 p. m. 29 4851 W. b. w. 2 1 1 9 a. m. 29 23|5* S. E. 2 1 1 p. m. 29 2051 S. S. W. 3 12 9 a. m. *9 355° N. 2 1 1 p. m. 29 52 49 N. I 13 9 a. m. 29 22 49 S. E. 2'" 1 1 p. m. 29 H 50 w. 2'" 14 9 a. m. 29 34 50 w. 2" 1 1 p. m. 29 50 5i S. w. 2 15 9 a. m. 29 54 51 S. 2 1 1 p. m. 29 57 51 W. b. s. 2 16 9 a. in. 29 53 50 s. s. w. 2' 1 1 p. m. 29 635° s. w. 2 n 9 a. m. 29 2« 51 s. 2 1 1 p. m. 29 32 50 s. w. 2 18 9 a. m. 29 38 51 s. w. 2 1 r p. m. 29 67 5 1 s. w. 2 9 a. m. 29 67 51 s. w. 2" 1 1 p. nr . 29 68 SI s. s. w. 3 20 9 a. rn • 29 26 5 1 s. E. i" 1 1 p. in. 29 A 51 s. w. 3 21 9 a. m. 29 32 51 S. E. 2 1 1 p. m. 29 *4 49 s. 2 22 9 2. m. 29 43 W. b. N. 2 1 1 p. m. 29 65 48 w. 2 23 9 a. m. 29 80 48 s. 1 1 1 p. m. 2 9 «7 49 W. b. N. 2 24 9 a. m. 29 86 5° w. 2' 1 1 p. m. 3^ 5 5° W. b. N. 2 25 9 a. m. 29 74 51 s. w. 2" 1 1 p. in. 29 70 5 1 w. 2 26 9 a. m. 29 5i 51 s. w. 2"' n p. m. 29 44 5i s. w. * 3 27 9 a. m 29 5C 5 2 N. W. 2" 1 1 p. m. 29 56 51 N. W. 2" 28 9 a. m 29 6' 49 N. N. W. 2" 1 1 p. in. 29 9c 49 N. N. W. 2" ' Total 94 [ +50 ] Rain Weather 600 Hazy fhowers through the day Cloudy Hazy weather, with rain till 1 p. m. Cloudy, but afternoon fair T hunder fhowers heavy, with fqualls Showery .770 Rain conft. from 11 a. m. thro* the d. (Rain, with very heavy fqualls Slight fhowers, with fun-fhine between I Clear and ferene Rain conftant j hazy, w. var. to S.W. .990 Heavy fhowers (Hail ftorms, with heavy fhowers (Cloudy .670 Rain very heavy till the afternoon jClear |Cloudy, with fmall rain at times |Cloudy weather .450 Rain conftant till 2 p. m. [Showery |Rain till noon .420 Showery ; but clear for the moft part .Clear Rain in the night very heavy .7 10 Rain conftant through the day |Hail-ft. with moft heavy fqualls of w. •3CoFair, with fun-fhine Rain fince 5 p. m. Fair Showers in the even, at prefent clear Clear .7 16 Cloudy ; in the night, heavy rain Rain drizling through the forenoon Cloudy Rain conftant till 3 p. m. Showery Rain drizling conftant through the day Rain; wind at S. W. a ftorm Black and cloudy weather ; but little r. D° Showery in the morn, afterw. Hail-ft. Show, at times ; but fair for the moft part .510 .284 Remarks N. B. The ma- chine is placed ft® of eddy winds, it i very confiderable iiJ fiance from mi building, except tc the North, wHU however, it is fan feet did ant, uut from that quartet tea have little or n rain. 94O or near 10 inches of rain in 39 I I 3 ^Avrv 3 XA faiuft ; :' '■ IfiOD 3fb 4! A. (iMGimlli ! JOB ^ Art 3’. ') I dm {'i'‘< sldth^ ; jnur'inH ■ ! jJ' Phi/cs. Trans. JUMP/. TABJOty^ 45 /. ,. ^ , C 45* j Received Auguft, 1 7<^7» XLIV. Defeription of an EleElrometer in- vented by Mr. Lane ; with an Account of fame Experiments made by him with it : In a Letter to Benjamin Franklin, LL. D. F. R.S. Alderfgate-Street, O&ober 15, 1766. S I R, Read Nov. 26, E I N G employed in fome eleCtri- >767* cai enquiries about the beginning of the year 1762, it occurred to me, that many experi- ments on this fubjeCt might be made with a much greater degree of precifion, if we could determine, with any tolerable accuracy, the comparative quan- tity of elettric fluid, with which, for any given ex- periment, the coated phial is impregnated. An inftrument, which I have contrived for this purpofe, may not improperly be called an Electro- meter. I have herewith fent you a drawing thereof [Tab. XX.] with the machine * to which i have fixed it. •* This portable machine is the contrivance of Mr. Read, mathematical inftrument maker at Knightfbridge, near London. M m m 2 Figure C +5 2 I Figure i„ A. The cylindrical glafs of the machine, ufed inftead of a globe.1 The cylindrical part of the glafs is fix inches in length, and fixteen in circumference. 13. The wheel, at every turn of which the cylindri- cal glafs revolves four times. C. The conductor. D. The coated phial. E. A brafs wire loop, palling through the wood work to a tin plate, on which the coated phial Hands.. F. The pillar of the Electrometer made of wood, bored cylindrically about ^ of its length, and rendered eleCtrical, by being long baked in an oven, and then boiled in linieed oil, and again baked. At fir ft the pillar was made of brafs, which, though it ferved very well to determine the eleCtric ftroke for medical purpofes, yet was defective in many experiments, as the ta- ble thereby became a ready conductor. G. Brafs work, having its lower part inclofed within the bore of the pillar, H. A ferew, which paffes through the brafs work near the bottom, and fixes it in the pillar. I. A groove for the ferew H to move in, when the Electrometer is moved higher or lower, as the different heights of different condenfing phials may require. K„, A well polifhed bemifpherical piece of brafs, fixed to the conductor.. ‘ k ’ * - ’ . L. A [;4S3 3 L. A fteel fcrew, patting through the top of the brafs work, whole" threads are diftant nearly of an inch from each other. M. A well polifhed fpherical piece of brafs, fixed to the fcrew L, and oppofite to K. The polilh of K and M will often be deft royed by large eledrical explolions, and it Ihould again be reftored, particularly where the experiments require accuracy. N. A fcale, with divifions equal to each turn of the fcrew. . . . O. A circular plate fixed to, and moving with the fcrew, pointing at each turn to the divifion upon the fcale. This plate is alfo divided into twelve, to denote the parts of each turn. The principle on which the Eledrometer ads is very fimple, being merely this ; the coated phial is hereby rendered incapable of accumulating and re- taining any more than a certain quantity of the eledric. fluid, for any intended experiment, when a metallic or non-eledric communication is made from the fcrew H to the wire loop E of the ma- chine, and that quantity will be proportionate to the difiance of K and M from each other, and confe- qucntly the explofion and firoke will thereby be re- * Thus if a perfon holds a wire faftened to the fcrew H in one hand, and another wire fixed to the loop E in the other, he will perceive no firoke, n K and M are in contad, notwithstanding the cylim*' drical glafs-A ads ftronglv. But if, by. turnings fcrew L, the ball M is diftant from K PaK ot * an 3 [ +54 ] an inch, a very fmall ftroke will be perceived, with an explofion from K to M; and if K and M are diftant one inch from each other, the quantity of the dearie fluid, at the time of the explofion, will be increafed too times : for example, it appears by experiment, that, if the explofion happens after 4 turns of tjie wheel B, when M is diftant from K t*t of an inch, or 1 turn of the ferew j the fame will happen at 8 turns of the wheel, when M and K are diftant 2 turns of the ferew, or of an inch j and if K and M are diftant 3 turns of the lerew, the turns of the wheel will be 1 2 at the time of the explofion ; the fame proportion will conti- nue fo far as the diftance of K and M is equal to the condenfing power of the coated phial without wafting. By wafting, I mean when the phial is fo fully charged, that part of the eledtric fluid efcapcs from the mouth of the bottle, or from the conductor into the air, or to fotne adjacent non-eledtric. The number of turns of the wheel, when K and M are at any of the above diftances, will be more or lefs in. proportion to the ftate of the air, the cylindrical glafs, the cufhion againft which the glafs is rubbed, or the coated phial ; which laft will not give fo great an explofion when the air is damp as when dry. The fewer the number of turns of the wheel, at any given diftance, the better the machine worketh. Thus a comparative difference between any two machines may be determined. A wire in general is better than a chain, unlefs the chain is held very tight ; particularly in very fmall ftrokes, the eledtric fluid will be loft in palling from link to link of the chain. By •n. [ 455 ] By experiment it alfo appears, that the quantity of electric fluid, at every explofion, will be propor- tionate to the quantity of coated glafs, either as to the fize of tthe coated phial, or to the number of phials added. For example, if the phial D has half of the coating on each fide of the glafs taken off, the explofion will happen after half the number of turns of the wheel, at any of the above diftances ; and if a phial, with twice the quantity of coated glafs, is employed inftead of D, the number of turns of the wheel will be double j the lame will happen if two coated phials, each equal to D, are ufed ; and if three phials, the number of turns will be triple, &c. ' The phial D, ufed in the following experiments, contains about 80 fquare inches of coating on the infide, and alfo on the outfide of the glafs; the mouth being flopped with wood, prepared like the pillar, and the coating not too near the mouth of the phial, to .prevent the eleCtric fluid’s waiting, and thereby the phial may be more fully charged. As K is part of the conductor, and of M the elec- trometer, the diflance between them is the diflance of theiele&rometer from the conductor ; whence it will be readily underftood, when 1 relate the diflance of the electrometer, in any experiments. For ex- ample, the electrometer at 20, that is, M, is 20 turns of the fcrew diftant from K, or 4.® of an inch. That lightning and electricity are of very near affinity, if not the lame, evidently appears from the many difcoveries you have made ; and as the follow- ing experiments tend to confirm the fame, as well as 7 to [ 456 1 to ill aft rate the ufe of the eledrometer, I hope they will not be unacceptable. Experiment I. I [» f i . n |f « i i 3' • 1 * 1 ■ * ^ A piece of moift tobacco-pipe clay, rolled cylin- drically , a. fig. 2. about an inch in length, and about 2 or X of an inch in diameter, having a piece of wire thru ft into each end, b b , diitant about of an inch from each other, with the folid clay between, and the end of one of the wires, c c , fixed to the loop of the machine E, and the other fixed to the final 1 ferevv of the eledrometer H, will, with an explofion at 20 of the eledrometer, be inflated as in fig. 3. or if the clay is too dry, or the quantity of eledricity too great, it will burft in pieces, leav- ing only the clay concave near the ends of the wires ; and though the experiment will in appearance differ, yet it will always leave evident figns of an ex- plofive power, or fudden rarefadion, excepting when the wires in the clay are at too great a diftaftce from each other; then the eledric fluid will only run over its moift furface. If, inftead of clay, a mucilaginous vegetable pafte is ufed, as wheat-flower and water, 6cc. the experiment will appear the lame. Experiment II. Take a piece of common tobacco-pipe hard- baked, as ufed for finoaking, about an inch ip length ; fill the bore with clay, and put wires into each end, as in fig. 2. which applied in the lame manner to the machine, will bui lt into many pieces, at C 457 ] _ - at 20 of the electrometer ; fometimes the pieces will he driven near ten feet from the machine* Experiment III. A fmall fquare piece of Portland done, with holes drilled at each end fo as to admit the wires, was in like manner bur ft in pieces, when a fecond coated phial was added to increafe the ftroke* The iron cramps in ftone buildings are fimilar to the wires, and when a building is ftruck by light- ning produces a fimilar effect. I obferved, that when the tobacco pipe, or ftone, was damp, the experi- ment fucceeded better than when dry ; and 1 fre- quently found, that either of them, after being firft dipped in water, would be broken with a lefs explo- fion than before. This obfervation is different from the received opinion of many, not well acquainted with elec- tricity, that lightning is lefs likely to do mifehief af- ter a fhower of rain than before : fo far may be true, that the rain will bring down fome of the lightning* and alfo render thatched houfes, &c. lefs likely to take fire, but will not affift buildings that have me- tallic ornaments near their tops, as the weather- cocks of churches, &c. As a metallic conductor from the tops of build- ings to the earth will prevent the effedts of light- ninp' on them, fo will the fmalleft wire prevent the effects of electricity on the ftone, or tobacco-pipe, when in contadt with the two wires, c c, fig. 2. Vol.LVII. Nnn If [ 458 1 If the tobacco-pipe, inflead of clay, is filled as above, with an electric fubflance, as wax, pow- dered glafs, or with any non-eledtric fubflance, in- ferior to metals as a condudlor, it will be burfl in pieces with nearly the fame quantity of the eledhic fluid. As the above experiments fucceeded better when the flone or clay were previoufly dipped in water than before, I was induced to try water only. Experiment IV. Having made a hole, without any cracks on the fide, through the bottom of the phial, a , fig. 4. which may eafily be done if the phial is conical at the bottom, as in the figure, by holding the phial inverted in one hand, and with the other finking a pointed fleel wire againfl the apex of the cone. Through this hole I palled a wire, b , and filled the bottom, c, with melted fealing wax, leaving the other end of the wire out, at d ; when the wax was cold, the phial was about 1 filled with water, and flopped with a cork, through which a wire, e> was pafied downwards, till the points of the two wires were diflant from each other about _V of .an inch, as near as my eye could determine a wire from the eledlrometer was fixed to e, and another from the loop of the machine was fixed at d j by an ex- nlofion, at 20 of the eledlrometer, the phial burfl * I in 3 [ 4-59 ] in pieces, the top falling from the bottom near the point of the lower wire. Another phial was fitted in the fame manner, and the cork cut longitudi- nally, that the air might freely pafs at the time of the explofion, but this made no fenfible difference : often times the phial is fo cracked as to refemble radii from a center. If oil is ufed inftead of water, the event will be the fame. The quantity of eleCtricity neceffary to burft the phial, appears to vary more in proportion to its thicknefs than its fize ; many phials of various fizes may be broken at io of the electrometer, while others, nearly of the fame fize, remain found, with a ftroke at 30, or even more. I generally found green glafs more difficult to break than white. When the phial is not broken by the eleCtric ftroke, the agitation of the water may be fenfibly obferved at the inftant of the explofion, and the eleCtric fpark evidently feen to pafs through the wa- ter, from the point of one wire to the other. This remarkable appearance of the eleCtric fluid’s pafling through water may be obferved, when the electrometer is at a fmaller diftance from the con- ductor, if the wires are nearer to each other. I have broken many phials by the eleCtric ftrokes as above-mentioned, when the wires have been at the various diflances, of above 1 inch to of an inch from each other, as near as my eye could de- termine ; but the diftance of about _L. of an inch I ufually prefer. N n n 2 The [ 46° ] The above experiments I have often repeated, and may therefore be relied on : want of leifure has pre- vented me from purfuing them more minutely. But I hope they will lerve as hints to others of more abili- ties and leifure, than Your refpedful humble fervant. T. Lane. Received [ 46 1 ] Received in October, 1767. XLV. Of the Increafe and Mortality of the Inhabitants of the If and of Madeira. By Dr . Thomas Heberden, F. R. S. Read Nov. 26, TT T HEN I confider the number of Vt people in the Madeira, and the Rate of the inhabitants, I know no place more pro- per for forming an eftimate of the increafe and mortality of mankind, than this ifland j for the number of perfons is upwards of 6o,ooo, all of whom may be fuppofed to live and die in the fame place where they received their exiftence ; the ac- ceftion of ft rangers and the egreftion of the natives being fo equally inconfiderable, that if the one doth not exadtly counterbalance the other, the difference may juftly be negledted, as of no confequence in the general calculation. This has excited my curiofity; and, by myintereft with the vicar-general of this diocefe, I have pro- cured a furvey from houfe to houfe in each of the refpedtive parifhes ; from which, and the parifh regifters, I have deduced the adjoined account. An Hypothefts. The number of perfons in this ifland, in the year I743> W2S 4^ 2 34 °f fevcn years old and upwards, o Now [ 462 ] Now fuppofing the minors were in the fame pro- portion then, as in this prefent year, the total of ihe inhabitants was 53,057. Therefore, by the rule of anatocifm, they have increafed at the rate of 1.0082 per cent . per annum ; and by the fame rule do double in 84 years 4 months and 25 days. From an exadf furvey, made in the beginning of the year 1767, the number of inhabitants on the illand of Madeira, was as follows ; Perfons of feven years old and upward Perfons under feven years of age 58669 5945 Total 64614 Chriftened Anno Males Fem. 1759 102 I 905 1760 I 198 I I 1 I 176 I 1035 1022 1762 1 128 II25 1763 ms 1115 1764 1 1 1 2 io85 1765 ti83 ii43 1766 I 172 n38 8967 8644 Buried Males Fem. 542 643 83 7 662 54o 620 618 506 594 7*3 9°9 7°4 578 7°5 649 53i Wedd. 43 8 421 513 491 476 469 495 462 4968 5383 Total 17611 10351 Chridcned Chriftened in 8 years Buried in 8 years C 463 ] 17611 Medium for each year 2201 l 10351 Medium for each year 1293^ Oclennial increafe 7260 Annual increafe 9°7# Proportion of the yearly births to the number of perfons, as — - ■ ■ of the yearly burials to the number of perfons, as ... of births to burials - - of males born, to females - ■— — ■1 ■■ ■■ — of females buried, to males - — — 1 to 29,35 1 to 49,89 too to 58,77 100 to 96,39 108,33 to 100 Weddings each year, at a medium Proportion of Weddings to births, as I ■ ■ ■ ■ of Weddings to burials, as I 470 £ to 4,68 to 2,75 Mortality of the Seafons. Winter January 93 February 84 March 132 3°9 Spring Summer April 108 July 129 May 105 Auguft 135 June 120 September 84 333 348 Autumn October 87 November in December 84 282 The mortality of fpring and fummer, to that of autumn and winter, as 115 to 100. N. B. This calculation of the mortality of the feafons is not deduced from the whole number of Inhabitants on the ifland, as I could not procure authentic materials to proceed with exadt- nefs; the number of the perfons, from which it is calculated, is 6880. Received [ ] Received November 19, 1767. XLVI. An Account of fame very large FoJJil 'Teeth, found in North America, and de- ferred by Peter Collinfon, F. R . S. 1 .* Read Nov. 26,^ Perfwade myfelf it will not be unac- I767‘ Jj[ ceptable to this Learned Society, to receive the beft intelligences I can collect of the teeth, and bones of elephants, found in North America, in the year 1766, which are now offered for your infpection. George Croghan, Efquire, who is a deputy of Sir William Johnlon, the King’s fuperintendant of In- dian affairs in America, in the courfe of his navi- gation down the great river Ohio, after puffing the Miame river, in the evening came near the place where the elephants bones are found, about four miles fouth-eaft of the Ohio, and about fix hundred miles diftant from and below Pitfburgh, from the neareft fea-coaft at lead feven hundred miles; Next morning he met with a large road, which the buf- faloes had beaten, wide enough for two waggons to go a-breaft, leading ftrait into the great licking- place, to which the buffaloes and all the fpecies of deer refort, at a certain feafon of the year, to lick the earth and water from fait fprings, that are impreg- nated with nitreous particles ; whether to clean le their C 465 ] their ftomachs, or for what other purpofe, is fub- mitted to the fentiments of the Society. Efquire Croghan had been here fome years before, and gave fome account of the monftrous bones, and teeth, found at this place, called by the Indians The Great Buffaloes Lick ; but being now more at leifure, he carefully examined all its furrounds, and difcovered under a great bank, on the fkirts of the Lick, five or fix feet below the furface, open to view, a prodigious number of bones and teeth, fpe- cimens of which now lie before the Society, be- gging to fome of the largeft-fized animals ; by the quantity, he computes there could not be lefs than thirty of their fkeletons. By their great teeth, or tufks, of fine ivory, fome near feven feet long ; every one that views them, I believe, will not hefitate to conclude they belong to elephants. It is very remarkable, and worthy obfervation, none of the molares, or grinding teeth of elephants, are difcovered with thefe tufks j but great numbers of very large pronged teeth of fome vaff animals are only found with them, which have no refem- biance to the molares, or grinding teeth, of any great animal yet known. As no living elephants have ever been feen or heard of in all America, fince the Europeans have known that country, nor any creature like them; and there being no probability of their having been brought from Africa, or Afia; and as it is impoffible that elephants could inhabit the country where thefe bones and teeth are now found, by reafon of the feverity of Vol. LVII. Ooq the [ +66 ] the winters, it fecms incomprehenfible how they came, there. I conclude, many of this learned Society are not unacquainted with the foflil elephants teeth annually found in Siberia, lodged in the banks of the great river Oby, and other rivers of that country. On the fyftern of the deluge, it has been con- jectured, that, as the extenlive kingdom of Siberia lies behind the native country of the elephants in Alia, from Weft to Eaft, and to the North, by the violent adtion of the winds and waves, at the time of the deluge, thefe great floating bodies, the car- cafes of drowned elephants, were driven to the Northward, and, at the fubfiding of the waters, depo- sited where they are now found. But what fyftern, or hypothecs, can, with any degree of probability, account for thefe remains of elephants being found in America, where thole creatures are not known ever to have exifted, is fubmitted to this learned Nov. 4, 1767. p. S. The Bifliop of Carlifle prefented to the Royal Society, on the 27th of February, 1766, fome foftil teeth and bones from Peru, which have fome analogy with the before-mentioned, not fo re- cent, but much more petrified ; the pronged teeth are like to agate. A Lift • ^ [ 467 ] 1 A Lift of the Teeth and Bones fent over by George Croghan, EJquire, February 7, 1767, from Phi- ladelphia. To Lord Shelburne. Two of the larged; tufiks, or teeth, one whole and entire, above fix feet long, the thicknefs of common elephants teeth of that length. Several very large forked or pronged teeth 5 a jaw-bone, with two of them in it. To Dodtor Franklin. Four great tulks, of different fizes. One broken in halves, near fix feet long. ^ One much decayed, the center looks like chaik, or lime, 1 , A part was cut off from one of thefe teeth, that has all the appearance of fine white ivory. A joint of the vertebra?. Three of the large pronged teeth ; one has four rows of fangs. Befides the above, Captain Owry, an Officer who ferved in the country during the laft war, now living at Hammerfmith, hath a fmall tufk, as ii of a calf elephant, the furface of a fine finning chef nut colour, and a recent look; and a great pronged tooth, larger than any of the above, which were alfo brought from the fame licking place. O o o 2 XLVII. C 468 ] XLVII. Sequel to the foregoing Account of the large Foffil "Teeth . By P. Collinfon, F. R. S. Read Dec. 10, T N my obfervations on the long teeth l?b7' £_ and grinders, at the laft meeting of this Society, I forebore giving my fentiments on thefe remains of great animals found at the Great Lick, near the river Ohio, being willing the Society fhould determine for themfelves. As I perceived one of the long teeth, or tufks, was channelled or ribbed, near the larger end, I was in fome doubt, if peculiar to the elephant. To fatisfy myfelf, I went to a warehoufe, where there were teeth of all forts and fizes for fale j on examin- ing them, I found as many ribbed or channelled, . as plain and fmooth, fo that now, I have no difficuty to pronounce them, agreeing in all refpe&s, with the elephants teeth from Africa and Afia. But as the biting or grinding teeth, found with the others, have no affinity with the molares of the elephant, I muff conclude, that they, with the long teeth, belong to another fpecies of elephant, not yet known ; or elfe that they are the remains of fome vaft animal, that hath the long teeth, or tufks, of the elephant, with large grinders peculiar to that fpecies, being different in fize and fhape from any other animal yet known. I had one of thefe grinders, that weighed near four pounds, with as fine an ena- mel on it, as if juft taken out of the head of the creature. The \ TbUos. Trans.ToJ.IML. TAB XXKjr 464 [ 469 ] The elephant is wholly fupported by vegetables > and the animal to which thefe grinding teeth belong, by their make and form, feemed defigned for the biting and breaking off the branches of trees and fhrubs for its fuftenance ; and if I may be allowed to conclude from analogy, that the great heavy un- weildy animals, fuch as elephants, and the rhino- ceros, &c. are not carnivorous, being unable, from want of agility and fwiftnefs, to purfue their prey, fo are wholly confined to vegetable food ; and for the fame reafon, this great creature, to which thele teeth belong, wherever it exifts, is probably fup- ported by browfing on trees and Ihrubs, and other vegetable food. Explanation of the Fig. in Tab. XXI. and XXII. Tab. XXI. is a fide view of a large pronged tooth, that weighed three pounds and three quarters, and was eighteen inches round, and four inches thick. It is now in the poffeffion of the Right Honourable Earl Bute. A. A. A. The prominences of the top or crown. B. B. B. The prongs by which it has been faftened in the lockets. Tab. XXII. reprefents the top of the tooth; A. A. A. are the finus’s, or concavities between B. B. B. and C. C. C. or the two rows of prominences that form the crown of the tooth. XLVIH. A C 47° ] XLIX. A Catalogue of the Fifty Plants from Chelfea Garden, prefented to the Royal Society by the worfhipful Company of Apothecaries, for the Tear 1766, pur- suant to the DireBion of Sir Hans Sloane, Bart . Med. Reg. et Soc . Reg. nuper Prrcfes : By William Hudfon, Societatis Regime & clariff. Societatis Pharmaceut. Lond. Soc . Hort. Chelfean. PrafeBus et PrccleBor Botanic. • 0 • • • • • * • * Read Dec. 10, 2 201 \ GroftlS fplCd VCTlti , petalo ex- j767- /~\ teriore exferente a rift am rec- tam ftridtam longiflimam. Lin. Sp. pi. ed. II. 91. Hudf. FI. Angl. 26. Gramen fegetum altiftimum, panicula fp'arfa. Bauh. pin. 3. 2202 Agroftis mil ea, petalo exteriore arifta ter- minali redta ftridta mediocri. Lin. Sp. pi. ed, II. 91. 2203 Aira C(?fpitofay foliis planis, panicula patente, petalis bafi villofis ariftatifque, arifta re&a brevi. Lin. Sp.pl. ed. II. 96. Hudl. H. Angl. 29. Gramen fegetum, panicula arundinacea Bauh. pin. 3. Theatr. 35. 2204 Aira ■ [ 471 ] 2204 Aira caryophyllea , foliis fetaceis, panicula divaricata, fioribus ariftatis diftantibus. Lin. Sp. pi. ed. II. 97. Hudf. FI. Angl. 31. Giamen paniculatum, locuftis purpuro-ar- genteis, annuum. R. Syn. 407. 2205 Alopecurus pratevfis , panicula cylindrica fpi- ciformi, glumis villolis, culmo eredo. Hudf. FI. Angl. 23. Alopecurus culmo fpicato eredo, glumis vil— lofts. Lin. Sp. pi. ed. II. 88. Gramen phalaroides fpica molli. Baub. pin. 4. 2206 Alopecurus agrejlis, fpica cylindrica longifii- ma, glumis glabris, culmo eredo. Hudf. FI. Angl. 23. Alopecurus culmo fpicato credo, glumis nudis. Lin. Sp. pi. ed. II. 89. Gramen typhoides, fpica anguftiore. Bauh. pin. 4. 2207 Alopecurus genicidatm, culmo fpicato infrado. Lin. Sp. pi. ed. II. 89. Hudf. FI. Angl. 24. Gramen aquaticum geniculatum fpicatum. Bauh. pin. 3. 2208 Alopecurus bulbofus , fpica cylindrica,. culmo eredo, radice bulbofa. Hudf. FI. Angl. 24. Gramen myofuroides nodofum. R. Syn. 397. 2209 Alopecurus Movfpt'licnjis , panicula fubfpicata, glumis fcabris, corollis ariftatis. Lin. Sp. pi. ed. II. 80. Gramen alopecuroides Anglo-britannicum max- imum. Bauh. pin. 4. 2210 Alopecurus paniceus , panicula fubfpicata, glu- mis villolis, corollis ariftatis. Lin. Sp. pi. ed. II. 90. 7 Gramen C 472 ] Gramen alopecurum minus, fpica virefcente divulfa. Barr. ic. 115. f. 1. 2211 Anthoxanthum cdoratum, fpica ovato-oblonga, flolculis fubpedunculatis arifta longioribus. Lin. Sp. pi. ed. II. 40. Hudf. Fi. Angl. 10. Gramen pratenfe fpica flavefcente. Bauli. pin. 3. 2212 Avena fativa, paniculata, calycibus difpermis, feminibus laevibus. Lin. Sp. pi. ed. II. 1 1 8. Avena alba. Bauh. pin. 23. 2213 Avena nuda^ paniculata, calycibus trifloris, re- ceptaculo calycem excedente, petalis dorfo ariftatis. Lin. Sp. pi. 1 1 8 . Hudf. FI. Angl. 41. Avena nuda. Bauh. pin. 23. R. Syn. 289. 2214 Avena fatua , paniculata, calycibus trifloris, flolculis omnibus ball pilofis, ariftis totis Ja?vibus. Lin. Sp.pl. ed. II. 118. Kudf. FI. Angl. 41. Avena fylveftris pilofa, ariflis rccurvis. Hill. Ox. III. 209. t. 7. f. 5. 2213 Avena fragilis , fpicata, flofculis fubquaternis ' calyce longioribus. Lin. Sp. pi. ed. II. 119. Gramen loliaceum ipurium hirfutum, ariftis geniculatis, Barr. ic. 905. f. 1, 2, 3. 2216 Briza eragroflis, fpiculis lanceolatis, fiofculis viginti. Lin. Sp. pi. ed. II. 103. Gramen paniculis elegantiftimis. Bauh. pin. 2. Hift. Ox. III. 204. t. 6. f. 52. 2217 Briza pi mat a, fpica difticha, fpiculis ovate - lanceolatis. a Gramen [ +73 1 Gramen filiceum, paniculis integris. Eocc. Sicil. 62. t. 33. f. 2. 22 iB Bromus fecahnus , panicula patente, fpicuiis ovatis, ariftis redis. Lin. Sp. pi. ed. II. Hudf. FI. Angl. 39.. Gramen avenaceum fegetate majus, gluma targidiore. Hid. Ox. III. t. 7. f. 17* 2219 Bromus mollis , panicula erediufcula, fpicis ovatis, ariftis redis, foliis moliiftime villofis. Lin. Sp. pi. ed. II. 112. Gramen avenaceum pratenfe, panicula fqua* mata et villofa. Hift. Ox. III. 213, t. 7. f. 18. 2220 Bromus rube?is , panicula fafciculata, fpicuiis fubfeffiiibus villofis, ariflis eredis. Lin. Sp. pi. ed. II. 1 14. Gramen panicula molli rubente. Bauh. hift. IL 266. , . 2221 Bromus giganteus , panicula nutante, lpiculis quadriftoris ariftis brevioribus. Lin. Sp. ph ed. II. 1 1 4. Hudf FI. Angl. 40. Gramen fylvaticum glabrum panicula recuvva. Vaill. parif 93. t. iB. f. 3. 2222 Bromus diflachyos , fpicis duabus eredis alter— nis. Lin. Sp. pi. ed. IT. 115* Gramen fpica brizse minus. Bauh. pin. 9. Pluk. Phyt. t. 33. f. 1. . 2222 Cynofurus criftatus , bradeis pinnatindiS. Lin. Sp. pi. ed. II. 105. Hudf. FI. Angl. 47.^ Gramen criftatum. Bauh. hift. II. Syn. 398. Vol. LVII. Ppp 2224 Cy- [ 47+ ] • ■ - 2224 Cynofurus echinatus , bradeis pinnato-paleaceis ariftatis. Roy. Lugdb. 64. Lin. Sp. pi. ed. II. 105. Hudf. FI. Angl. 47. Gramen alopecuroides fpica afpera. Bauh. pin. 4. 2225 Cynofurus aureus , paniculas fpiculis flerilibus pendulis ternatis, floribus ariflatis. Lin. Sp. pi. ed. II. 107. Gramen panicula pendula aurea. Bauh. pin. 3. theatr. 33. Scheuch Agr. 149. 2226 Fefluca elatior , panicula fecunda ereda, fpi- culis linearibus muticis, floris planis. Hudi. FI. Angl. 37. Gramen loliaceum, fpica divifa, pratenfe majus. Hid. Ox. III. 184. t. 2. f. 15. 2227 Fefluca pratenfis , panicula fecunda ereda, fpiculis linearibus muticis, floris planis. Hudf. FI. Angl. 37. Gramen paniculatum elatius, fpicis longis mu- ticis et fquamofls. R. S. 41 1. 2228 Fefluca fuitans , panicula ramofa ereda, fpi- culis fubfeflilibus teretibus muticis. Lin. Sp. pi. ed. II. 111. Hudf. FI. Angl. 38. Gramen aquaticum cum longifhma panicula. Bauh. hilt. II. 490. R.S. 412. 2229 Fefluca bromoides , panicula fecunda fpiculis eredis la^vibus calycis altera valvula inte- gra, altera ariflata. Lin. Sp. pi. cd. II. 1 1 1. Hudf. FI. Angl. Gramen paniculatum bromoides minus, pa- nicula ariflatis unam partem ipcdtantibus. R. Syn. 415. 2230 Fefluca [ 475 ] 2230 Feftuca ovina , panicula fecunda coardlata ariftata, culmo tetragono nudiufculo, fo- liis felaceis. Lin. Sp. pi. ed. II. 108. Hudf. FI. Angl. 36. Gramen capillaceum, locuftis pennatis non ariftatis. Pluk. ph. t. 34. f. 2. R. Syn. 410. 2231 Holcus fpicatus , glumis bifloris muticis flo- ribus geminis penicillo involucratis, fpica ovato-oblonga. Lin. Sp. pi. ed. II. 1483. Gramen paniceum fylveftre maximum, In- dian orientalis. Pluk. Phyt. t. 32. f. 4. 2232 Holcus Sorghum, glumis villolis, feminibus ariftatis. Lin Sp. pi. ed. II. 1484. Milium arundinaceum, fubrotundo femine, forgho nominatum. Bauh. pin. 26. Hift. Ox. III. 196. t. 5. f. 7. 2233 Hordium murinum, fiofculis lateralibus maf- culis ariftatis, involucris intermediis ciliatis. Lin. Sp. pi. ed. II. 1 25. Gramen fecalinum chalepenfe, radice tuberofa. Hift. Ox. III. 179. t. 6. f. 7. 2235 Lolium temulentum , lpica ariftata, fpiculis compreflis ariftatis. Lin. Sp. pi. ed. II, 122. Lolium fpica ariftata, radice annua. Lin. Sp. pi. 83. Hudl. FI. Angl. 44. Gramen loliaceum, fpica iongiore. Bauh. pin. 9. Theatr. 1 2 1 . 2236 Lolium perenne , fpica mutica, fpiculis com- preflis multifloris. Lin. Sp. pi. ed. II. 122. P p p 2 Lolium C 4-76 3 Lolium fpicis muticis, radice perenne. Lin. Sp. pi. 83. Hudf FI. Angl. 44. Gramen loiiaceum anguftiore folio et fpica, Bauh. pin. 9. Theatr. 121. 2237 Melica cilia? a , flofculis inferioris petalo exte- riore ciliato. Lin. Sp. pi. ed. II. 97* Gramen avenaceum montanum lanuginofum. Bauh. pin 10. pr. 20. 2238 Melica nutans , petalis imberbibus, panicula nutante fimplici. Lin. Sp. pi. ed. II. 98. ITudf. FI. Angl. 3 1. Gramen avenaceum locuftis rarioribus. Baub. pin. 10. 2239 Panicum patens, panicula oblonga patente, ca- lycibus bifloris, foliis lineari-lanceolatis. Lin. Sp. pi. ed. II. 86. Tfiama-pullu. Hort. Mai. XII. 75. t. 41. 2240 Panicum miliaceum , panicula laxa flaccida, foliorum vaginis pubefeentibus. Lin. Sp. pi. ed. II. 86. Milium femine albo et luteo. Bauh. pin. 8. Theatr. 139. 2241 Panicum roerticillatum , fpica verticillata, ra- cemulis quaternis invocellis unifloris bi- fetis, culmo diffufo. Lin. Sp. pi. ed II. 82. Gramen paniceum fpica fimplici. Bauh. pin. 8. Theatr. 139. 2942 Panicum 1 liride, fpica tereti, involucellis bi- floris fafciculato-pilofis, feminibus nervofis. Lin. Sp. pi. ed. II. 83. Hudl. FI. Angl. 21. Gramen 1 [ 477 ] Gramen paniceum, fpica fimplici. Bauh* pin 8. Sch. Agr. 46. 2243 Panicum colonum , fpicis alternis fecund is mu- ticis ovatis leabris, rachi teretiufcula. Lin. Sp. pi. ed. II. 84. Gramen paniceum minus fpica divulfa infuls Barbadenfis. Pink. Ph. t. 1 8 p . f. 5. 2244 Phalaris canarienfis , panicula lubovato fpici- formi : glumis carinatis. Lin. Sp. pi. ed. II. 79. Phalaris major, femine albo. Bauh. pin. 28. 2245 Phalaris utriculata , panicula fpicata, petalis arifta articulata, vagina fupremi folii fpathi- formi. Lin. Sp. pi. ed. II. 80. Gramen pratenfe, fpica purpurea ex utriculo prodeunte. Bauh. pin. 3. Theatr. 44. 2246 Phalaris arundinaeea , panicula oblonga ven- tricofa. Lin. Sp. pi. ed. II. 80. Hud!. FI. Angh 21. Gramen arundinaceum fpicatum. Bauh. pin. 6. Theatr. 94. 2247 Poa ciliaris , panicula glomerata, glumarum valvulis interioribus pilofo-ciliatis. Lin. Sp. pi. ed. II. 102. Gramen pratenfe, fpicis brevibus muticis lo- cuftis minimis. Sloan. Hift. Jam. I. 114. t. 73. f. 1. 2 2 48 Poa Er agrojits , panicula patente, pedicellis flexuoiis, lpiculis ferratis decemfloris. Lin. Sp. pi. ed. II. 100, Gramen [ 478 ] Gramen phalaroides, fparfa brizae panicula, min. Barr. Ic. 44. f. 2. 5249 Poa rigida , panicula lanceolata fubramofa, floribus alternis lecundis. Lin. Sp. pi. ed. II. 102. Hudf. FI. Angl. 35. Gramen exile duriufculum in muris et aridis proveniens. R. Syn. 410. 2250 Poa cotnprejfa , panicula fecunda coar&ata,' culmo obliquo compreflo. Lin. Sp. pi. ed. II. 10 1. Hudf. FI. Angl. 33. Gramen paniculatum, radice repente, cul- mo compreflo. Vaill. parif. 91. t. 18. f. 5. Received C 479 ] Received November 12, 17 67. XLIX. An Account of fome neutral Salts made with vegetable Acids, and with the Salt of Amber \ which fews that vegetable Acids differ from one another ; and that the Salt of Amber is an Acid of a parti- cular kind , and not the fame with that of Sea Salt , or of Jd itriol , as alledged by ma- ny chemical authors . By Donald Monro, M. D. Phyfician to His Majefys Ar- my, a?id to Saint George’s Hofpital. R R. S. Title read December 17, 1767. Read. January 14, 21, rflROUGH no fubftances have and 2S, 1768. B 1 ,, r , ' been more generally ufed, both for the prefervation of health, and the cure of difeafes,- than vegetable acids, yet hitherto they have been examined with fo little care, that it has been, the common received opinion, that they were all nearly of the fame nature, at lead: as to their che- mical properties, and poffeffed nearly of the fame virtues ; but the following account of neutral falts, made with thefe acids, and the foffii or mi-, neral alkali, (hews that they differ materially from one another. 1 But [ 4^0 ] Previous, however, to entering into the account of thefe falts, it will be proper to mention fome few things relative to falts in general. Simple falts are commonly divided into acid and alkaline. The acid are reckoned four in number* 1. The vitriolic. 2. The nitrous. 3. The marine, or muriatic. 4. And the vegetable. The alkaline three. 1. The vegetable, or that which is got from the afhes of mod; vegetable fubdances. 2. The foffil, or mineral, called likewife foda and natrum, which is got either by burning certain ma- rine plants ; or from fea fait 5 or in the bowels of the earth. 3. The volatile, which is got either by putre- faction, or by the force of fire, from mod animal fubdances ; or by didillation from mudard feed, and fome other particular vegetables. The acid are didinguifhed from each other, by their tade, fmell, and other properties, but principally by their forming different neutral falts with the lame alkali. And the alkaline are known likewife from one another, by their forming different neutral falts, when joined with the fame acid. Hence when we find acid , or alkaline falts, in different bodies, if we faturate each with the lame alkali, or 7 with [ 4«i ] with the fame acid, according as the original fait is of an acid, or of an alkaline nature, and find upon difiolving, evaporating, and cryftallifing the neutral falts, that they are all of the fame kind, we con- clude, that the original acid, or alkali, was the fame in all ; but if we obtain different neutral lalts from each, we conclude that the original acid, or alkali,' was different in each. It there are no more alkaline falts in nature, than the three already mentioned ; and if there were no more acids than four 5 then the number of neutral falts would be confined to the twelve marked in Dr. Cullen’s Table ; but it will appear from the follow- ing experiments, that inftead of one, there are many vegetable acids ; and that, therefore, the number of true neutral falts muff be greatly multiplied *. * Dr. Cullen’s Table of neutral Salts. Acid Alkaline Neutral Salt Acid Alkaline Neutral Salt Vitriolic V egetable Foffil Volatile Vitriolic Tartar Glauber Salt Vitriol. Ammoniac Marine or Muriatic V egetable Foffil Volatile Sal. digeft. Svlvii Common Salt Common Ammoniac Nitrous Vegetable Foffil Volatile Common Nitre Cubic Nitre Nitrous Ammoniac Vegetable Vegetable Foffil V olaiile Regenerated Tartar Rochelle Salt Spiritus Miudereri Dr. Vogel, Profeflbr of chemiftry in the univei fity of Got- tengen, in his Inftiturioncs Chemiae, publifhed in 1752, gives a table of . neutral falts, which comprehends the twelve men- tioned bv Dr. Cullen, with the addition of three or four more. He fee ms to believe, that the acid of vitiiol forms a different neutral fait with the pot-afh, and with. the alkali procured from nitre. lie mentions three falts, made with the vegetable alkali VoL. LVII. Qjj q Many [ 4^2 ] Many chemifts have affirmed, that the vitriolic is the only original acid in nature ; and that the nitrous and marine are only this acid changed into different forms by foreign mixtures ; and Dr: Boerhaave *, Vogel “f*, Macquer f:, and moft late chemifts, feem to think, that as all trees, plants, and other vegetable fubftances, receive their nourifhment from the bowels of the earth, therefore their acids are only fome of the mineral changed into a different form by the ve- getative procefs ; and that they all approached in their nature either to the vitriolic, the nitrous, or the marine : and as the neutral falts, produced from the mixture of the vegetable alkali, with vinegar, cream of tartar, and other common vegetable acids, have a good deal of the fame external appearance, moft chemifts have concluded, that all vegetable acids were nearly of the fame nature ; though fome few have fufpedted, that they might be found to differ from one another, and to have different degrees of affinity, if they were examined with care ; and to confirm this, Dr. Vogel § tells us, that if fome of the Rochelle falts be thrown into a decodlion of tama- rinds, the alkaline bafts of the Rochelle fait will unite with the acid of the tamarinds, and the cream of tartar will be precipitated. . and vegetable acids ; to wit, with vinegar, cryftals of tartar, and lemon; and one with the native acid fait (as he calls it) of urine, and the volatile alkali, and one with the acid of tartar, and the volatile alkali. * Boerhavii Element. Chemiae, vol. I. 804. f Vogel, Inftitut. Chemiae, p. 2x5. fe£t. 468. Ed. II. j Macquer, Elemens de Chymie Theorique, chap. xvi. p. 240. § Vogel, Inftitut. Chemiae, p. 216. fcff. 469. As [ 4§3 ] As I always fufpeCted, from the tafte and fmell that vegetable acids differed materially from one another, and was the more confirmed in this opi- nion by the above experiment mentioned by Dr. Vogel, I began to confider whether fome method might not be fallen upon to determine this queftion ; and, on recollecting, that the Rochelle fait * con- creted into large folid cryftals, which preferved their figure long, even in the open air, though the tartarus tartarifatus -f* always appeared in the form of a powdery foliated fait, and run very foon per deli - qiuum , when expofed to the air, I imagined, that if we were to unite the foftil, or mineral alkali, with different vegetable acids, we fhould be able to ob- tain true neutral falts in form of regular cryftals; which would fhew how far thefe acids differed or approached to each other in their nature and proper- ties ; and, upon trial, found that I had judged right ; for each particular acid almoft yielded a neutral fait pecauliar to itfelf, of which I fhall now give a parti— culr account, and fhall range thefe falts under the following heads. 1 . Of neutral falts formed with native vegetable acids. 2. Of neutral falts formed with fermented vege- table acids. * The Rochelle fait is made with the cryftals of tartar, and the foflil alkali. f The tartarus tartarifatus, with the cryftals of tartar, and the fait of tartar ; fo that the only difference between thefe two falts is, that the one is made with the foflil, and the other with the vegetable alkali. Q_q q 2 3. of [ 4-8+ 3 3- Of neutral falts formed with diftilled vegetable acids. 4. Of neutral falts formed with flowers of benzoin and fait of amber. SECT. I. Of neutral falts formed with native vegetable acids , and the fojjil or mineral alkali . Experiment I. With the acid of lemons. The firft experiment I made was with the acid of lemons; fix ounces of the juice faturated rather more than three drams of the foflil alkali ; and upon evaporating the liquor to a pellicle, and letting it /land tor tome days, I obtained a fait compofed of a number of fmall cryflals of irregular figures ; fome appeared to be irregular fquares, or rhomboidal ; others irregular pentagons; others to have more tides ; but this general appearance was nearly what is repre- fented at a. a. a. &c. inTAB. XXIII. fig. 1. They were moftly flat, and not above 4 or of an inch thick ; though fome few were fomewhat of an oblong irre- gular cubical fhape, if I may be allowed to ufe the expreflion. Having obferved that the figure of neutral falts, made with vegetable acids, varied fometimes, ac- cording as they were cryftallifed in larger or lefs quantity, I got a quart of lemon juice, and faturated it with about two ounces, and two drams of the foflil C 485 ] foffil alkali. Before adding the alkaline fait in this experiment, I tried the temperature of the lemon juice with one of Fahrenheit’s thermometers, and found that the quickfilver flood in the tube at 54 ; upon removing the thermometer, I immediately added the alkaline fait; and as the folution was be- gun, I again put the thermometer into the liquor, and let it remain for above a minute, and the quick- filver funk above one degree ; fo that this acid gene- rates cold in the time of its uniting with the foffil alkali, though the neutral fait, produced from their union, does not affedt the thermometer in the time of its folution in water. The appearance of the fait obtained in this cry- flallifation was very different from what it was in the former. The whole was made up of an infinite number of chryflals, fo fmall that one at firfl could fcarce diffinguifh their figure; but on examination part feemed to be of the fame ffiape as the larger ones, got in the former procefs ; the others were very fmall oblong parallelograms, and they were every where interfperfed with a number of fmall longifh cryflals, which in many places lay acrofs each other, and formed a kind of lattice work. The general appearance of this cryflallifation is re- prefented by b. b. &c. in Tab. XXIII. fig. 1. and that of fome of the particular cryflals by c. c. c. The tafle of this fait is very mild, and rather pleafant, approaching a little to that of a very weak fea fait. E x PE- [ +86 ] Experiment II. With the acid of limes. The lime is a fruit of the fame genus as the le- mon ; its acid is (harper, and has a more agreeable flavour. From the near refemblance of thefe two fruits, one fhould have fufpe&ed that the neutral fait of both would have been almoft the fame ; but their appearance is fomewhat different, though perhaps upon more accurate trials they may be found to have nearly the fame virtues, and chemical properties. The firft experiment I made was with thejuice of a dozen and a half ol (mail limes; and the neutral fait, produced from thence, was of the fame (hape, figure, and appearance, as the larger cryftals ob- tained in the firft experiment with the lemons; only the cryftals were much fmaller, and fuch as reprefented by a. a. &c. fig. 2. But having afterwards procured three dozen of larger and finer limes, I got from them near three times the quantity of juice I had in the former procefs ;t and having fatu rated this with the alkali, evaporated and cryftallifed it, I obtained a fait very different in its appearance from the former; though, in other refpe&s, it feemed to be intirely of the fame nature. Its cryftals were of the fize, and fomewhat of the appearance, of barley corns, or grains of wheat, as at c. c. c. ; fome larger, fome fmaller ; and laid in an irregular man- ner, but fo as to form a beautiful cryftallifation, which is reprefented by bt b. b. fig. 2. [ 4§7 ] peared, at a little diftance, to be roundifh, but on examining, narrowly, their Tides were found to be made up of five or fix flat furfaces ; and ge- nerally one end of each cryftal was made up of two flattifh fides, which role like a wedge which did not come quite to a point, but left a ftnall narrow furface between. Thefe chryftals, in the mouth, imprefs at fir ft a very flight faltifh, and fo me what fweetifh cool tafle ; which is by no means unpleafant, and refembles a good deal that of the fait of lemons. They did not affed the thermometer in the time of their folu- tion in water. Experiments III. and IV. With the acid of Sevill oranges, and of peaches. It being late in the fummer before I made any ex- periment with the juice of the Sevill oranges, I could get none of this fruit but what had been long kept and was fhrivelled, in fo much that a dozen and a half of the oranges did not yield more than half a pint of juice, which had loft a great deal of its acidity, and faturated but a very fmall quantity of the alkali ; and on cryftalliflng I could obtain no other fait but a few very frnall cubical or fquare cryftals, luch as are reprefented by fig. 3. and fimilar to the fait got in an experiment I made with peaches, as may be feen in fig. 4. A faponaceous or mucous matter, with which thefe faturated juices abounded, feemed to prevent the cryftallifation of the falts. 4 As [ 48S ] As both the juice of the orange, and of the peadhes, was in fmall quantity, and not in the moft proper hate for yielding a neutral fait, thefe expe- riments ought to be repeated, before we can fay what is the natural figure and appearance of the falts, that may be got by laturating the juices of thefe fruits with an alkali. Experiment V. With the acid of currants. A quart of the juice of white currants, after be- ing faturated with about nine drams of the fofiil al- kali, and purified by repeated filtrations, was evapo- rated till a peilicle appeared ; being put into a cool place, and allowed to fland for two or three days, it yielded a number of fmall fquare flattifh cryftals, fuch as are reprefented by fig. 5. Many of them feemed to be exadt fquares, and in general they ap- proached nearer to this figure, than the cryftals of any of the other neutral falts I have hitherto met with. This fait approached in its tafte to that of the limes ; its cryftals were hard and firm, and did not run per deliquium. Experiment VI. With the add of goofeberries. « A quart of the juice of goofeberries, being treated in the fame way, as that of the currants, yielded a neutral 7 [ 4^9 ] neutral fait very different in its appearance, from any of thofe hitherto mentioned. Its bafis, or what adhered to the tea-cup, was made up of a number of very fmall roundifh or fquarifh cryflals; which formed an incruftation thicker than a {lulling ; from which grew up a number of very line, thin, tran- fparent plates, of irregular fhapes ; they were nar- rower at the bafis than above j and in fome meafure might be compared to the fcales of a fmall ffh, or the wings of flies, fet on their edges at a little diftance from one another ; in forne places the plates arofe from the fides of others ; and in others they appeared fomewhat like the fine leaves of very fmall plants. In fig. 6. we have different view's of this fait ; a . a. reprefents a piece of cryftallifed fait viewed from above ; b. b. a profile view of the thin plates {landing on their bafis ; c. c . the bafis itfelf ; and the letters d. a view of the thin plates laid on their flat fides. Experiment VII. With the acid of apples. Having got two dozen of codling apples, I cut them to pieces, put them into a large earthen veflefl and poured three quarts of water upon them ; and then diflblved above two ounces of the fofiil alka- line fait in the water, and let them fiand for fix days ; on examining, I found the water to be nearly in a neutral flate ; it did not ferment on the addi- tion either of an acid or of an alkali. I then fil- tered the liquor through paper, and evaporated it, Vol. LVII. R r r till t C 49° ] till it was reduced to about five or fix ounces, when it became thick, and a pellicle began to form on the fur- face. I then fet it in a cool place, to allow the halts to concrete. After two days were elapfed, it was covered with a blueifh variegated faline cruft 5 immediately below which was a clay coloured faline matter, which refembled wet earth or hand, that had been raifed by fmall worms ; and this was interfperfed every where with fmall flattifh globules of the fame fort of matter ; below this was a purplifh jelly, inter- 1 pel fed with a whitifh or afh coloured faline matter, formed into irregular longifh flat plates, which looked more like a compofition of lalt and earth than a pure fait. The appearance of this faline mat- ter made me fufpedt, that it was mixed with fome fort of oil, which the alkaline fait had extracted from the fkins of the apples, which I had forgot to peel oft before infufing them in water ; I therefore got a frefh parcel of codling apples, which I caufed to be carefully peeled, and then treated them in the fame manner as the former, and obtained the beau- tiful fait painted in fig. 7. which refembled a good deal the fait of the goofeberries j being compofed of a number of fmall roundifh very delicate tranfparent plates, ftanding on one edge, on a fine faline cruft, which adhered every where to the ftdes of the china bafon ; and were intefperfed with a grey coloured faline mat- ter. The cryftals of this fait were in general rather fmaller, rounder, and more of a fize, than thofe of the goofeberry; and I did not obferve any rifing from the lides ot others as in it; and they feemed to be dilpofed in a more regular uniform manner. The [ 49i ] The letters a. a. &c. reprefent pieces of this cry- ftallifation viewed from above ; b. b. &c. fome of the fine plates laid on their fide ; c. c. and e fome of the afh coloured plates obtained in the firft operation ; d. d. fome of the brown clay coloured faline matter; f* the flattifh globules, which befet every where the infide of the pellicle, that was on the top. After the cryftallifation of the fait in this fecond procefs, the liquor which remained was poured into another fmall china bafon ; and, on being evaporated, exhibited nearly the fame appearances as had been obferved in the firft procefs. Experiment VIII. With the acid of wild forrel. In order to fave the trouble of a tedious evapo- ration, by faturating this acid mixed with the other juices of the plant, I procured fome of the effentiai fait of the wild forrel, from Mr. Heineken, apothe- cary in Duke-ftreet ; which I difiolved in boiling water, and faturated with the alkali ; and by evapo- rating obtained a beautiful pure white neutral fait, which is reprefented by fig. 8 ; a. a. fhews a part of the cryftallifation where the fait (hot into longifh cryftals, refembling fomewhat the fmall ones of nirre; none of them exceeded the length of half an inch ; b. b. other pieces of the cryftallifation, which had a different appearance ; c. c. a piece where it ap- peared like a fmall granulated fait ; d. d. fome fmall roundifh or fquare cryftals, which adhered like R r r 2 a cruft [ 492 ] a cruft to the Tides of the tea-cup j e> e, e. detached cryftals. Experiment IX. With the acid of tamarinds. Having had a prefent of Tome tamarinds in pods, from Mr. Arch. Glofter, praditioner in phyfick in Antigua, I took out the pulp, and put about two pound of it into three quarts of water ; and then fa- turated its acid with the alkali, and, after filtrating the liquor, I evaporated it to the confidence of a fy- rup, and then put it into a cool place for 24 hours j when I found that a cryftallifation had actually taken place, I feparated the fait from a thick fweetifh liquor of the confidence of a fyrup ; after it was dried, it had the appearance of a piece of common mofs, made up of a number of fmall cryftals difpofed in an irregular manner, and mixed with vifcid or fac- charine juices. The letters a. a. &cc. of fig. 9. fhew Tome pieces of this fait while it remained in this form. As I fufpeded this fait to be ftill mixed with a vifcid matter, I difiolved Tome of it in warm water, and cryftallifed it anew, when it had a very dif- ferent appearance, for it had fhot into an infinite number of very fmall cryftals, which came every where from centres. The length of thefe cryftals did not exceed half an inch at moft ; they were no thicker than horfehairs, or common white thread. How many cryftals fhot from each centre I could not determine j but, in many places, the cryftalli- fation [ 493 ] fation rofe into fmall oblong, oval, or roundidi tufts, made up of an infinite number of the fmall crystals that fhot from the centre towards the circumference. Some of the concentrated liquor having been accidentally left in a faucer, and on the iides of a tea cup at night, next morning the liquor in both velfels had fhot every where into fmall fine cryffals, that came like radii from a centre; in fome places they had compleated the circle, in others only half,, and in others only the two oppof te quarters. I treated thr^e pound of Eaft-India tamarinds, which I bought in a fhop in Caftle* Street, in the fame manner ; only, after they were faturated with the alkali, and the liquor filtrated, it was fet by for fome weeks, and then filtered again before it was evaporated. The people of whom I bought thefe tamarinds told me, that there was no fugar mixed with them ; and I believe what they faid was true, for I obtained eafily a very pure and fine fait from them. Having at firft carried the evaporation too far, as foon as the liquor was removed from the fire, it immediately began to concrete in form of a number of fmall circles on the furface of the liquor, which were fuccefiively fucceeded by others, till the whole became one folid mafs; but on diffolving this mafs in water, and evaporating only a little, and fetting the liquor in a cool place to allow the falts to concrete, the cryftallifation began on the furface of the liquor, in form of fmall circles or liars, and I obtained a fait in every refpedt fimilar to the former. The general appearance of this fait is reprefented by b3 b, in fig. 9, and the different appearances in different parts of the cryftallifation by c> c. Expe-- / [ 494 ] Experiment X. With the acid of plums. Having got a quantity of the larger fort of the green plums, I caufed the ftones to be picked out, and the plums to be bruifed and put into a large china bowl; I then poured about two quarts of wa- ter over them, and faturated their acid with the fofiil alkali; after they had hood 24 hours, I /trained off the liquor, filtered, and evaporated it, till there remained only a few ounces, when it was fet in a cool place for four days, at the end of which time I found that a cryffallifation had taken place; but, upon pouring off the fuperfluous liquor, I could not obferve any general form of cryftailifa- tion ; the whole was made up of a number of very thin, flat, longifh cryftals, from about to 4 of an inch long, and from to 4 or 4 of an inch broad, of an irregular figure, laid without any particular form, and mixed every where with a mucous and black oily matter; when dry, the whole appeared like a confufed mafs, where however the form of fome of the cryftals was to be obferved, as is to be leen at a, a , in fig. 10 ; in fome places the cryftals feemed to be laid with their edges uppermoft, and in others in a different manner, as at b, b> &c. In order to know the regular and true form of the cryftaiiifation of this fait, 1 feparated a quan- tity of the pureft from the large mafs, diffolved it in boiling water, filtered it through paper, and cryftallifed it a fecond time in a tea cup. It now appeared in a more regular form; the cryftaiiifa- tion [ 4g5 ] tion was divided into four roundifh clumps, or clufters, which were feparated or diftinguifhed from each other by a furrow. Each clump was made up of a number of very fine delicate plates laid edgeways, in fomewhat of a regular manner; and between them a number of others, where part of the flat fides were to be feen, and amongif them an infinite number of fmali rhomboidal or roundifh cryftals ; the clumps appeared, in miniature, in the fun, fomewhat like to the lower part of the fpread tail of a peacock. The letters c, c, c , c , fhew the general form of the cryftallifation, d, d , d, the form and fihape of fome of the feparate cryftals.. I treated another parcel of plums of the fame kind in a different manner; I faturated part of the liquor when frefh, and let it ftand till a fermenta- tion had taken place before 1 evaporated it ; and I let the other half ftand till the fermentation was over before faturating it; but the fait obtained from both, appeared nearly in the fame form, though the number of clumps in this fecond cryftallifation was only three : and in a third experiment the appear- ances were exactly fimilar, only the fait did not divide into clumps. This fait taftes coolifh on the tongue, but does not affedt the thermometer, in the time of its folu- tion in water. In the prelent hard froft* fome of the fait of plums, which had been diflolved in three or four times its own weight of water, and let by in a clofet, cryftal- lifed anew. The cryftals were flat, thicker than a Ihilling, and moft of them had fix fides of unequal * N. B. The account of this laft part of the experiment was given in to the Royal Society in the beginning of January 1 768. lengths., [ 496 ] lengths, as reprefented by b, by in the figure marked large cryftals of neutral fait of plums, where they were run together, their figures were moft irregu- lar as at i, i j fome few lmall ones were fquares, as at b, k. Hence we fee what a variety the different methods of cryflallifation make in the figures of thefe falts. Experiment XI. With the acid of mulberries. Three quarts of the pure juice of the mulberry being faturated with four ounces of the fofiil al- kali, filtered, clarified with the whites of eggs and evaporated, yielded a faline matter, mixed with a quantity of a mucus and oil ; which, on being puri- fied as much as poflible, by lying on a fpongy brown paper, exhibited a very fine granulated fait almoft like fea fand, in which no regular-formed crvftals were to be obferved. Some of this fait being again diffolved in water, evaporated and cryftallifed a fecond time, appeared in the tea cup like a cake made up of the fame fort of fine granulated fait as reprefented at a, a , fig. 1 1 ; — and another parcel b , b> which was treated in the fame manner, though it at firft appeared rougher, and more of a cryftalline form, yet on examination was found to be made up of the fame fort of faline matter. — On taking out the cake, there were a few thin very fmall fquare cryftals, fuch as thofe marked c, c, c, auhering to the bottom of the tea cup. A (mall quantity of the faturated juice of the mulberries having been left by accident for ten or twelve _ [ 497 ] twelve days in different tea cups and china bafons, there formed in each a number ot figures, or fort of cryftals, refembling fomewhat tlie alphabet ot the Chinefe language, interfperfed with a few fmall, oblong, parallelogram-fhaped cryftals, as at d, d, d . Three quarts more being faturated with the al- kali, were allowed to ftand for five or fix weeks, and then filtered and evaporated to about feven or eight ounces ; the greater part of which was put into a ftone bafon, and about half an ounce into a fmall china bowl ; after ten days, the liquor in the bowl had (hot into a number of fmall thin cryftals, fuch as reprefented at e, e} e-,— -and that in the ftone bafon into a fine pure fait made up of fimilar cry- ftals, but thicker and larger, fuch as thofe at fff- — Thefe laft are certainly the true laft cryftals of this fait. Experiment XII. With the acid of grapes. A bafket of grapes, which were brought to market for ripe, though many of them were ftill hard and four, and not come to their full perfection, yielded three quarts of juice, which I filtered and faturated with two ounces and a dram of the fof- fil alkali:— after it had flood for a month to depu- rate, it was again filtered, and then clarified with the whites of eggs, and evaporated to about five ounces, when it became of the confidence of a fy- rup, and had fomewhat of a fweetifh tafte. It was then fet in a cool place for two days to cryftallife; but, inftead of forming any regular cryftals, it concreted in form of a faline matter, Vol. LVII. Sff refem- [ 498 3 refembling coarfe loaf fugar, when it firft concretes in a thick fyrup ; fome of which being dried on brown fpongy paper, became very white, and feemed to be made up of long, very fmall cryftals, no thicker than human hairs, and a faccharine matter. From this appearance, I judged that the fait was Fill mixed with a quantity of vifcid juices; and therefore I diluted the whole with a quart of New River water, depurated it again with the whites of eggs, and evaporated it to four ounces, which I fet in a cool place for eight days; and then, on examin- ing, I found that a cryftallifation had taken place, and I obtained above a dram of a pure neutral fait, made up of fmall, fquare, and cubic, and fmall narrow oblong parallelogram cryftals, re- fembling fomewhat in appearance thofe got from the juice of the mulberry, only the cryftals were lefs, as may be feen in fig. 12. After feparating this fait, I fet the remaining li- quor again in a land heat, and evaporated about half an ounce of it, and then put it for fome days into a cool place; and there formed a faline faccha- rine-like concretion, exa&ly fimilar to what was got in the firft trial. SECTION II. Of neutral Salts formed with fermented vegetable Acids , and the fojji l Alkali. Having {hewn a variety of neutral frits made with native vegetable acids, we come next to take a view of thofe made with fermented acids, and {hall begin with that produced from vinegar. E x p e- *_yf. l/a// o/^emo/iJ. — - QP& *' w ' ^ £ a ^ \ — a l&v jff ^ w 09*? -V " ' a ' •' » « * ’ *\,v *«J ,r • /$Ste * Ail/a//i>f: ./ finite, l/ff/.z. A'. 'Ja/Z-o/’C/roMi J& s. V#‘ *-AJa// <7/ /’ {. ,,/ /•,/,//,!. ■'/'//. '7- .’- #* <4£ .*« pu CD 0 t yt'fl /a// of • /irinrimi,/). -; -v 'usr' b , &c. and a profile view of a fmall piece at c , c> and a figure of fome of the plates laid on their flat fides at d, d. Did the difference of the age of the verjuice em- ployed in thefe two experiments, or the difference of the proceffes they underwent, make the difference in the appearance of the falts obtained in the diffe- rent cryffallifations ? The fait of the old verjuice approached to that of vinegar ; of the new to that of apples. Experiment V. With the acid of perry. At the time I gave in this paper, in the beginning of November, I had made feveral attempts to ob- tain a neutral fait from perry (or the fermented juice of pears) but without fuccefs, owing to the large quantity of faccharine juice with which this liquor abounds. But having accidentally left fome of the concentrated liquor in a fmall china bafon, on examining it fome days after the prefen t hard frofl: had begun, * I found that a cry flail ifation had taken place. The cryftais were flat, long, narrow, very thin tranfparent plates, fuch as reprefented in fig. 17; they were from a quarter of an inch to near an * The account of this experiment was given to the Royal Society about the middle of January 1768. inch. [ S°4 ] inch long ; they were moftly fixed to the fioes of the bafon by one end, many flood almoft upright, and others lay acrofs each other. One end was com- monly made up of two floor t files, which met at a point. They remained fome days expofed to the air in a cold room, and preferved their tranfparency and figure j but after they had flood for about a quarter of an hour in a warm room, while the painter was drawing the figure, they loft their tranfparency, and became white and mealy. They tailed cool, and fomewhat bitter in the mouth. SECTION III. Of neutral Salts , formed ‘with dijlilled vegetable Acids , and the fofjil Alkali . Acids diftilled from wood, and other vegetable fubftances, have been mentioned as a diftindt fpe- cies, but no proof has been brought of their dif- fering from the other vegetable acids ; on the con- trary, in the tables of neutral falts given by che- mifts, no notice is taken of any neutral falts made with thefe acids ; and therefore it is to be prefumed that they imagined them to be nearly of the fame nature with the others. In order to know if the'e acids differed from one another, and from the native and other acids, I had fome guaiac wood, fome fir wood, and fome honey diftilled, and procured fome of the acid of each, which I faturated, filtered, evaporated, and cryftallifed. Exp e [ S°S ] Experiment I. With the acid of guaiac wood. The cryflals of the neutral fait of guaic wood were long and final], and fhot like the rays of the fun from a centre, and appeared as reprefented in fig. 1 8. Experiment II. With the acid of fir wood. The neutral fait of fir had a very different ap- pearance; there were no fuch diftindt cryflals as in the other; what were to be obferved ieemed to be long and fmall, to come in many places from points, and to go in fomewhat of a circular man- ner, or to deferibe a curve, and appeared as repre- fented by fig. 19. Experiment III. With the acid of honey. It has been a doubt among naturalifts, whether honey fhould be ranked among the vegetable or the animal fubftances. Moll chemifls feem to think it fhould be ranked among the vegetable, and look upon it as made up principally of the juices of plants collected by the bees; but, however that mat- ter may be, the following is an exadt account of Vol. LVII. Ttt the [ S°6 ] the neutral fait made with the acid obtained from this fubHance by diHillation. In order to procure this acid, I prevailed with Mr. Winter, brother-in-law to Mr. Heineken, apothecary, to diftil four or five pounds of honey in a retort ; at fir ft he imagined that I only wanted the watry phlegm, which has been called by the name of the fpirit of honey, and flopped the riiftil- lation before the acid came over; but having di- Hilled a fecond quantity, he procured me about fix ounces of a very acid liquor, which I mixed with the phlegm or fpirit which he firfl brought me; I then faturated the whole with the foflil alkali, fil- tered and evaporated the liquor to a pellicle. After it had flood all night in a cool place, I found the pellicle to be compofed of a yellow, bitter, faltifh, mucous and oily matter ; below which was a dark purplifh liquor, which I poured into a tea cup, and there remained at the bottom of the flonegallypot, in which the evaporation had been performed, a yellow concreted matter, fomewhat of the appearance of yellow wax, mixed with a little honey; on the fur- face of which was to be obferved a number of glo- bules of the fame fort of matter, of the fize of mil- liard feeds; and interfperfed with a black very bitter fluff. Next day, on examining the dark coloured purplifh liquor which I had put into the tea cup, I found that a great part of it had concreted into a very beautiful fait, which is reprefented by fig. 20. a d) a, fhews the general form of the cryHallila- tion; b, b, b, b , the lhape, figure, and fize of fome of the cry Hals. The cry Hals were almoH all flat, and feerned in general to aflame the form of C 507 j long, narrow parallelograms, or longifh fquares, if I may be allowed to ufe the expreflion ; c> c , fome of the yellow faline matter. This fait is pleafant to the tafle, and evidently generates cold in the mouth in the time of its folu- tion; but I had not quantity enough to try with a thermometer what degree of cold it generated in the time of its fclution in water. SECTION IV . Of neutral Salts formed with Flowers cf Benzoin , and Salt of Amber. Experiments I. and II, With the flowers of benzoin. Mod; modern chemifls have looked upon the gum benzoin as a refinous fubflance, which bears the fame analogy to the vegetable refins, as the fucci- num or amber does to the foflil bitumens ; and they have edeemed the flowers of benzoin to be an acid fait, mixed with an oily and a fmall propor- tion of an earthy matter; but have brought no proof of its being fo. 1. In order to afcertain this fadt, I put twro drams and a half of the flowers of benzoin into fome water, and then dropped into it by degrees a folution of the foflil alkali ; every drop railed an ebullition or effervefcence, in the fame manner as when any common alkaline fait is throWn into an Ttt 2 acid L 508 ] acid liquor. I continued adding the alkaline lye till all ebullition ceafed, and the flowers were fully faturated and diffolved ; after which I filtered the liquor, and evaporated it till a pellicle began to ap- pear, and then fet it in a cool place all night, and next morning I had a fine pure tranfparent neutral fait, fuch as is reprefented by figure 21. It adhered to the china balbn in form of a faline cruft, which I removed; and on looking thorough it in the light, it feemed to be compofed of an infinite number of very fmall cryftals; above this lay, in many places, a number of cryftals of the figure of fmall oblong parallelograms, as thofe at b, b. But from the greater part of the furface of the cruft there arofe a number of very fine thin delicate plates of irregu- lar figures, {landing on one edge; lomewere fquares, others parallelograms, and others had more fides, the general appearance of which was fuch as is to be feen at the letters a, a , a , &c. This fait, when firft made, appeared as tranfpa- rent and clear as glauber fait, or nitre ; but on be- ing expofed to the air, became very foon white and mealy. In the time of the evaporation of this fait, a faline white mealy cruft rofe every where on the fides of the china bafon in which the operation was performed, and even came over fo far, as to cover its whole outfide. What rofe in this manner had a fweetifti tafte, and was not fo {harp in the mouth as what appeared in a tranfparent {aline form. The fuperfluous liquor, which remained after the cryftallifation was compleated, being put into a tea [509] tea cup, concreted in a very uncommon manner. In the middle of the tea cup it arofe fomething lilce a plant, or a fountain, where the water is dilcharged from a number of pipes, and fpread from the bot- tom of this, fo as to cover both the infide and out- fide of the cup, with a iweetiih, white, mealy, fa- line crufi, which in many places teemed difpoied like the fine fibres of plants, or of the leaves of trees. 2. Asa further proof of the flowers of benzoin being an acid of a particular kind, I latu rated tome of them with the fal volatile ammoniacum, evapo- rated and cryflallifed; and obtained an ammonia- cal fait, which had a very Angular appearance. It was covered on the top with a very white laline pellicle, below which were a number of thin, fiat,, white tranfparent cryftals, the greater number ot which feemed to be exadt fquares, fome few, oblong, parallelograms, fuch as are reprefented in fig. 22. The flowers of benzoin generated a considerable degree of cold in the time of their faturation with the volatile alkali; they funk the quickfilvei in the thermometer from 52 to 46. Experiments III. and IV . With the fait of amber. The fait of amber is now generally known to be of an acid nature ; but from what Mold. Bourdelin has laid of it, in the Memoirs of the French Aca- demy of fciences for the year 1742, ac^ „ been [ 5*° ] been looked upon by many chemifls *, to be ex- adly of the fame nature as the fpirit of fea fait, only mixed with a little of the oleum fuccini; — though l'ome have imagined it to be an acid of the vitriolic kind. i If, When I firft mixed this acid with the foffil alkali, I began to believe that what Monf. Bourde- lin had alledged was true ; for the liquor tailed faltifh, like to a weak folution of fea fait in com- mon water, but I was foon convinced of my error; for on evaporating and cryltalliling, I had a fait very different in its nature and properties from that of lea fait, or of glauber fait, one of which falts it mult have been had the acid been the marine or the vitriolic. This agrees with what Dr. Stockar de Neufornlj;, has laid of this being a particular acid. * Macqner Teems to be thoroughly convinced of the acid of fuccinum, or amber, being the fame with that of fea fait ; for in mentioning the proofs which Monf. Bourdelin has brought of its being fo, he fays, “ C’eft ce point qui eft l’objet principal de “ memoire de Monf. Bourdelin ; Sc cette decouverte eft fans “ contredit une des plus belles, Sc en meine temps des plus d if— “ ficiles, qu’il y eut a faire fur ce Bitume.” See his Elemens de “ Chymie pratique, tom. ii. p.213. t Sea fait is a neutral fait made of the foflil alkali, and marine acid, or fpirit of fea fait j and glauber fait, of the fame alkali and the fpirit of vitriol. J In the year 1760, Dr. Jo. Geo. Stockar de Neuforn, in his inaugural DifTeriation de Succino, publifhed at Leyden the 7th of July, 1760, proves by a number of experiments, that the add of fuccinum is neither that of vitriol nor of fea fait ; and he mentions two neutral falts made with this acid, the one with the common vegetable alkali, and the other with the volatile. He fays that the cryftals of the one, made with the vegetable alkali, are clear and pellucid, and of the fame figure as the The [ 5” ] The cryftals, I obtained in the firft experiment I made, were large and flat; and fuch as are to be feen at the letters a, a , 6cc. fig. 23; they were of no certain fbape or figure; fome were roundfth with a number of fides, others appeared fomewhat trian- gular, and others of different figures; and in fome parts the cryftallifation appeared like a piece of rock work. I diflfolved fome of this fait in water, and cryflallifed it a fecond time, but the cryftals were in general fmaller than in the firft operation ; and the cryftallifation appeared as reprefented by by by b. In order to fhew the difference between this and lea fait, I made Mr. Paul draw the figure of fome beautiful cryftals of fea fait, near to thofe of this neutral fait of amber. This fait is extremely different in its tafte from that of fea fait, and certainly likewife in its virtues and properties. 2. In order to afcertain more fully that the fal fuccini is an acid fui generis , I faturated fome of it with the volatile ammoniac fait, cryftallifed it, and obtained a neutral ammoniacal fait very different from that of the common fal ammoniacum; it was compofed of a number of fmall long narrow fiattifti cryftals, whofe fides were made up of four fiat fur- faces, fuch as thofe reprefented in fig. 24, and laid cryftals of the fait of amber itfelfj that it has a particular tafte, and diftblves eaftly in water, which the tartarus vitriolatus does not ; and when thrown on the fire, or put on a red hot non, crackles, and melts, bite )er remains fixed and neuter* Acids make no change on it, nor is aquafottis converted into an aqua regia by its mixture; it does i.ot precipitate fiiver from fpirit of nitre, though it precipitates lead from vinegar, in form of a white calx, which, however, cannot be changed into 2 faturnus corneas. C 5!3 ] in an irregular order. Tome lying acrofs others, and fome (landing on one end *. The fill fuccini generates a great degree of cold in the time of its laturation with the volatile al- kali, for it funk the quicksilver in the thermome- ter from 52 to 40; in this it agrees with the com- mon fal ammoniacum. The Conclufion. From the experiments above related, it is evident that phyficians have hitherto been in a great mif- take, in believing that all vegetable acids were nearly of the fame nature ; for from them it fhould feem that almoft each of the acids, called vegetable, has fomething peculiar to itfelf, and upon future trials may be found to have different virtues and properties •f'. The different appearance of the neutral falts above mentioned, from that of thofe produced by the union of the foffil alkali with any of the mine- ral acids, feems to make it doubtful whether the vegetable acids derive their origin from the mine- * Dr. Stockar de Neuforn fays, that this ammoniacal fait does not precipitate filver from aqua fortis, nor change aqua foitis into aqua regia ; and when put in a filver fpoon, and fet over the fire, it melts and flies off in form of a vapour. f However, it ought to be remarked, that when any of the concentrated faturated liquors ftood for ten or twelve days be- fore they cryftallifed, for the mod part fome cryftals of a flat, fquare, or of a narrow oblong parallelogram figuse, were found adhering to the Tides of the cup or bafon in which the liquor flood ; but whether this was owing to the alkaline bafis of tlicle falts, or to the acids approaching to each other in their nature, is what can only be determined by future experiments. l* ( ' ^ r?% ' _ ^4rnonoiuiiailJor^> vr(Zm/«r-. ^^/H/Homaca/'Jit// of /Sofb^oir? . 1 ♦ « « 1 >3 ■ i. .a mhC . fJ(i//<>/ rcr/ii /lrr/o//r t/edf. @&‘S /•/6'g* oVC-k ,*§&. I'is.. Ist* J>/,itos.Tntns.roUm.TABXaV: p.S‘2 jf, Hl/tult J-Ml/f'. J l'au/ ././<" . [ S13 ] ral; or whether they are not new fubflances, gene- rated either in the vefiels of plants by means of the vegetative procefs, or by fermentation, or by the force of fire. If they owe their origin to the mineral acids, they are certainly fo much changed in their virtues, and properties by the combination of new particles, and by the procefies they have undergone, that they may be looked upon as diftindt bodies in many refpedts. From what has been faid, it is evident that the number of true neutral falts * is infinitely greater than what has been fuppofed, of late, by chemifts ; and it is probable that many of the neutral falts, above de- fcribed, may prove to be excellent remedies in the cure of difeafes, as well as ufeful in many manu- factories. As there is fuch a variety of vegetable acids, and as each of them produces a diftindt neutral fait with each of the three alkalies, I think it would be right to diftinguifh them from one another by particular names ; the falts made with the vegeta- ble alkali may be called vegetable falts , as both th e acid and the alkali are vegetable fubftances ; thole made with the fofiil alkali neutral falts; and thofe made with the volatile alkali ammoniacal falts , as all the neutral falts hitherto made with this alkali have gone by this name. Thus we _ may call the three neutral falts made with lemon juice : i . Ve- getable fait of lemons. 2. Neutral fait of lemons. 3. Ammoniacal fait of lemons. * By true neutral fait is meant, a fait made with an acid and one of the three alkalies ; the word true is added to thefe falts, to diftinguifh them from neutral falts, made with earths or me- tals, and acids. p Vol LVir. U U u by '( 5r4 ] By means of thefe neutral falts we may be ena- bled to difcover many of the properties of vegetable acids, and particularly the different degrees of affi- nity or attraction between them and alkaline falts ; thus, for example, if we diffolve in water fome of the neutral fait of currants, and add fome lime juice or fome vinegar, and then evaporate and cryftal- lize: if we obtain a neutral fait of currants, we conclude that the acid of currants has a greater affi- nity or attraction to the alkali than the acid of limes or of vinegar; but, if we get a neutral fait of limes, or of vinegar, we conclude that thefe acids have a greater affinity with the alkali than the juice of currants. As I am fenfible that this account of vegetable neutral falts is very incomplete, and that I have done little more than given a very fuperficial defcrip- tion of their external appearance; and as it will probably require a length of time, and the labours of many, to difcover fully their virtues and proper- ties, I (hall recommend it to thofe who may pro- fecute this fubjeCt to endeavour to afcertain the fol- lowing fads : 1. What degree of cold or of heat is generated on the mixture of each acid with the different alka- line falts ; and likewife to try the fame experiment with each neutral fait at the time of its folution in water. 2. What quantity of pure alkaline fait it takes to faturate any determined quantity of each of the vegetable acids. 3. What figure each neutral fait aflumes when it is firft cryftallifed, and likewile after it has been purified. [ 5*5 ] purified, and again diflolved in lifed. water and crydal- 4. What quantity of water it takes to diffolve any determined quantity of each fait. 5. What effects thefe falts or their folutions in water have on oils, fulphur, ardent fpirits, metals, earths, and other fubdances ; what fubdances they mix eafily with, and to what bodies they prove a mendruum, or affid in diffolving. 6. How fai they agree in their virtues and pro- perties with the neutral falts made with mineral acids, and with each other. 7. What effects they have on the human body; ■whether they promote more particularly the perfpi- ration or the fecretion by the kidneys, or whether they a 61 more readily on the bowels, and promote the difcharge by dool ; and to afcertain the exa6t and proper dofes of each. # 8. And laftly, what effedts fermentation and di- ftillation have on native vegetable acids; and to ob- ferve and compare the appearances of the neutral falts made with thefe acids in their different dates: viz. 1. In their native date. 2. When made into wine. And ^dly, when made into vinegar; and likewife when made with acids brought over by the force of fire, or diddled from the fame juices in each of the three different dates mentioned. And in order to facilitate their labours, I fhall conclude this long paper with obferving, id. That all vegetable juices ufed for making neutral falts ought to be drained through a cloth, and then filtered through paper, before they are faturated with the alkaline fait; and that, after they U u u 2 are [ 5l6 3 are faturated, they ought to be allowed to hand for fome days, and fome of them for weeks, and then be filtered again, before they are evaporated. 2dly, That it is of ufe to clarify many of thefe juices, after being faturated, with the whites of eggs. 3dly, That it is fometimes eafier to obtain a neu- tral fait, by evaporating with a boiling heat, than with a flow or gentle fire; as the heat of boiling water coagulates, and throws up a quantity of vif- cid juices to the furface, which cannot be eafily feparated by any other means. qthly, That the fweeter any fruit is, and the more it abounds with faccharine or vifcid juices, the more difficult it is to obtain a neutral fait; and for this reafon I have not hitherto been able to get any neutral fait from the faturated juices of pears, or of cherries. 5 thly. That, in cafes where we are obliged to employ water mixed with the fruits cut final], in- ffead of their juices, it is right to peel off the fkins before we attempt to faturate the acid ; otherwife the alkaline fait is in danger of uniting with, and rendering foluble in water, the grofs oils with which the fkins generally abound, which afterwards pre- vent the cryftallifation of the neutral falts. Received [ 5*7 1 Received November 1 9, 1767* L. Experiments on the Dift illation of Acids , volatile Alkalies , Me. foewing how ^ they may he condenfed without Lofs> and how thereby we may avoid dif agreeable and nox- ious Fumes: In a Letter from Mr. Petei Woulfe, F. R. S . to John Ellis, Ffq\ F. R. S. Title read December 17, 1767* SIR, Read Feb. 4, TN the common manner of diftiilation i76S. 1 there efcapes a great quantity of fumes, which cannot be condenfed ; and in feveral opera- tions thefe fumes are very hurtful to the lungs, by the following method of diftiilation thefe fumes are totally condenfed, which makes a great faving m fome diftillations, and the operator is in no danger of being hurt by any pernicious vapours. This new method confifts in making the fumes pafs by a fmall glafs tube through water, which hereby becomes charged with the vapours, that would otherwife efcape. Defcription [ 5i8 ] Defcription of the apparatus. Tab. XXV-. Fig. i. A a retort. B a receiver, with a fpout at bottom, for the di~ ililling liquor to run into the bottle C; the recipient has alfo a fmall opening on one fide at D. E a crooked tube and 4- of an inch bore. F a veffel containing water. The crooked tube E is fitted to the fpout D of the receiver by means of a cork with a hole in its middle, and then well covered with lute; the other end of it goes to the bottom of the veffel F, to the mouth of which it is fitted by a cork, with a lemi- circular notch in it as at G, but without any lute to fallen it, as there muft be a fmall vent for the efcape of the elaftic air, and this is the only vent in all the apparatus for that purpofe. By this apparatus the fumes are obliged to pafs through the water in F, and there depofit all they contain, except their elaflic air. In mofl diflillations there is a quantity of air ab- forbed at different times during the procefs; and in this cafe the external air would prefs on the water at F, and force it by the tube into the veffel C, which might fpoil the diflilled liquor. This may be prevented by letting air into the receiver or bot- tle C, by boring a hole through the lute; this how- ever may be inconvenient, on account of the con- flant attendance which isnecelfary; but the fol- lowing apparatus will prevent it. See figure 2. It confifls C SJ9 ] eonfifts in fitting an empty vefiel H, to the appa-- ratus defcribed before. See figure i. By this means the water is forced into H, and by the ftopper at L it may be emptied, and put back into the vefiel F, the crooked tubes D and I are fitted to H, by a cork with two oppofite femicircular notches as at; K, and then well covered with lute.. Experiment I. On the diftillation offal ammoniac with quick lime. 12 lb * of Britifh fal ammoniac, and 26 th of quick lime were powdered, mixed, and put into the iron body A (fig. 3.) ; and when the apparatus -f- was luted, a gallon of water was poured on it through the orifice (b), which was immediately flopped ; the lime growing hot produced a vaft quantity of ela- ffic air, which though highly charged with volatile alkaly was condenfed by the water in F, fig. 2. the air only efcaping at the top of this vefiel with hardly any fenfible volatile alkaline fmell. Next morning, all being cold, another gallon of water was added as before, and a very flow fire made under the body for 14 hours, in which time there diftilled near a pound of volatile alkaly; the fire was then made itronger, and continued in that ftate for twelve hours more, in which time there was obtained, together with what was firft diftilled, 8 lb 4 of volatile alkaly, ftrong and fit for Eau de luce; this was taken out of the bottle and fet apart. The veflels being cool, * In all the experiments averdupois weight was made ufe of. f The fpout of the ftone head belonging to the body A, figure 3, is to be luted to the receiver B, figure 2. two C 52° ] two gallons more of water were put into the body, and the fire made as before, and continued till there was 7 lb diftilled of weak volatile fpirit; this an- fwers better than water for a frefh diftillation of fal ammoniac and lime. During the firft 16 hours of the diftillation, there continually efcaped through the water of F elaftic air very (lightly charged with volatile alkaly, efpe- cially when the water grew hot; but during the remaining time of the diftillation, no elaftic air was fet free. Two ftone gallon bottles, with three quarts of water in each, were made ufe of to condenfe the va- pours ; and when one bottle was grown warm by the fumes, the other was put in its place, while it was a cooling in a vefiel of cold water ; and fo con- tinually changed during the whole operation. The fix quarts of water encreafed by this means 2 lb and 4. in weight; and, by the following experiments it appears, that a pound of this vapour condenfed in the water is to a pound of the volatile alkaly, which was fet apart for Eau de luce, as 140 to 76, which is nearly twice as ftrong ; therefore there was a fav- ing of near lb of volatile alkaly, which would have been loft in the common manner of diftilla- tion, The water of the two ftone bottles charged with alkaline vapours was mixed, in order to reduce . them to the fame degree of ftrength, and as much of it was put into a glafs cucurbit as contained four ounces of the alkaline vapour; four ounces of the volatile alkaly, which was fet apart for Eau de luce was put into another cucurbit of the fame fize. 1 [ 521 ] and diluted with water to the fame volume of the other. This laft took i lb 3 5 of acid of vitriol, diluted with water, to be faturated, and did not grow hot; wheras the water containing the four ounces of al- kaline vapours took up 2 lb 35 of the fame acid of vitriol, and grew fo very hot, that the veffel could fcarce be held in the hand, even after having been diluted at different times with two quarts of water. This fhews that there is a great difference in the two, and that it is not intirely owing to ftrength. The heat produced by the vapours paffmg through the water, was tried at another diftillation, and raifed the quickfilver in Fahrenheit’s thermometer to 1 10 degrees. In rectifying cauftic volatile alkaly with lime, there is likewife a very great quantity of elaftic air fet free, highly charged with volatile alkaly, which condenfes in water and heats it. Water may be fo ft rongly charged with this vapour, that it will make very ftrong Eau de luce, nay, much ftronger than that which we laid before was diftilled and let apart for Eau de luce : but it is neceffary, as mentioned before, to make ufe of two done bot- tles, changing them as often as they grow warm. Experiment II. On the diftillation of the acid of fait by means of the acid of vitriol ; for the apparatus fee fig. 2. * A green quart retort coated with loam was made ufe of for this experiment, and it was placed * What goes by the name of a quart retort holds better than two gallons of water. Vol. LVII. x x X HI [ 522 ] in a reverberatory furnace on a naked fire ; 14 th of common fait was put into it, and on that the like quantity of oil of vitriol, which had been diluted the day before with 7Tb of water; the retort was then immediately luted to the recipient, and the didillation conducted in the common manner: the operation continued 16 hours, when hardly any more liquor would come over with a drong fire. To condenfe the vapours, two done gallon bot- tles with three quarts of water in each were made ufe of, as in the former experiment. In this operation there was obtained 9 lb 5 5 and 7 of fpirit of fait, which dropped into the bottle C; the fix quarts of water in the done bottles in- creafed in weight 61b 125 and 7; the caput mor- tuum weight 18 Tb 6 fo that in this operation there was only a lofs of eight ounces, which is but part of the whole, which probably was modly eladic air. Experiment III. The fame operation was repeated with a dower fire, which continued for 23 hours, after which time hardly any more liquor would come over with a drong fire. There were here produced n lb io§ of fpirit of fait, in the bottle C ; the fix quarts of water in- creafed in weight 3Tb io§, and the caput mortuum weighed 19 th 4§; the lofs was the fame as in the foregoing experiment. In order to know the different degrees of drength of the acids produced in thefe two experiments, they [ 523 ] they were faturated with a fixed alkaly diffolved in water. Four ounces of the acid in experiment II, which diflilled into C, took of the alkaline liquor to be faturated i3d 53 2’^- As much of the water * in experiment II, as con- tained 4 ^ of vapour took to be faturated 1^95, Four ounces of the acid in experiment III, which dropped into C, took of the fame alkaline liquor to be faturated 1 2 J 7. As much of the water of experiment III, as contained; four ounces of vapour •f took to be faturated 2ft 6 Four ounces of oil of vitriol, which was to wa- ter in weight as 24 to 13, took of the fame alkaline liquor to faturate it £ lb 10 § 75, which fhews that oil of vitriol is not fo flrong an acid as the vapour of fpirit of fait, when condenfed in water and di- flilled flowly, as in experiment III. From the foregoing experiments it appears, that 1 fb of the fpirit of fait vapour, condenfed in the water in experiment II, is to 1 lb of the acid of fait, which dropped into C of the fame experiment, as 200 is to 109, which is near double; and therefore the 61b 12^ and 7 of the vapour, which condenfed in the water, is equal very nearly to 13ft 1 5 of the acid which is diflilled in C : fo that by this method of diflillation, this great proportion of acid is faved, and thofe difagreeable fuffocating fumes avoided. * The water of the two bottles was mixed together; for they were of different ftrength. 4 The water of thefe two bottles were likewife mixed toge- ther for the fame reafon. X X X 2 In f 524 ] In experiment III, ifc of the acid vapours, which condenfed in the water is to i ft of the acid of fait which dropped into C, as 131 is to 50 or as 2 3 1 to 1 ; and therefore the 3 lb 10 l of acid va- pours, which condenfed in the water, is ahnolt equal to 9ft and 7 °f wliat mt0 J* . It further appears, that the flower the diftillation is conducted, the more concentrated are the acid vapours that condenfe in water. In order to ee whether there was any difference in the ftrength of the acid vapours, which were condenfed in the water from the firft to the laft of the diftillation, the following experiments were made. Five pound of common fait, with 5 th of oil ot vi- triol were diftilled in a tubulated retort, and three bottles with an equal quantity of water in each were made ufc of to condenfe the vapouis. The firft bottle increafed in weight 3 3, and during this time, which was twelve hours, there was no fire under the retort; that bottle being taken away, another bottle put under, a fire was made; this bottle increafed in weight 1 lb and halt an ounce, the third bottle increafed 10 g and a half. As much water of each of the three bottles as contained one ounce and a half of the acid fumes was faturated with an alkaly diffolved in water. The water of the firft bottle took to be faturated 1 1 5 2 * The fecond bottle took up 10 a 2 3 The third bottle < # 10 5 x3 An ounce and half of oil of vi- triol, which was to water, as 226 to 1 1 8 nearly, took up of the fame alkaly 75 3 dram. 29 3 By [ 525 ] By which it appears that the fumes, which firfl: arofe without fire, are ftronger than the fecond, and the fecond than the third. It appears further, that the moft concentrated portion of the acid of fea fait is the moft volatile, and that in ftrength it is to the oil of vitriol men- tioned before, as 44 "t t0 31* * In order to try the purity of the acid vapours, which were condenfed in the water, and of the acid, which diftilled into the bottle C, the follow- ing experiments were made, and are marked a, b, c, d. (a) Four ounces of the fpirit of fait of the 2d experiment, was perfectly faturated with 4^ of whiting. (b) Four ounces of the fpirit of fait of the 3d experiment, was perfectly faturated with 4J oi ditto. (c) As much water as contained 4 g of vapour of the 2d experiment, was faturated with 5 ^ of ditto. (d) As much water as contained 4 J of vapour of the 3d experiment, was faturated with 6 J of ditto. The reafon of ufing more whiting with fome than with others, was on account of the different ftrength of the acids ; and as there was a greater quantity of whiting than neceflary ufed in thefe experiments to faturate the acids, the undifiolved * This depends on the property of the acid of vitriol, and the acid of fea fait, combined with a calcareous earth ; for. this earth, combined with the acid of fea hilt, forms a very foluble fubftance ; whereas the fame earth, with the acid of vitriol, forms a fubftance infoluble (or almoft io), called felenite. part [ 526 ] part muft confid of whiting; and, if any acid of vitriol in the acids, of whiting and felenite. In order to feparate the felenite from the whit- ing, a large portion of diddled vinegar was made uie of, which diflolves the whiting, it being a cal- careous earth ; and in order to promote the folution, heat was made ufe of. The undiflolved part of (a) being perfectly fatu- rated with a lufficient quantity of diddled vinegar, and afterwards repeatedly wadied with pure water, and dried, weighed 4 oz. and 26 gr. (b) treated as (a) weighed 4 oz. and 52 gr. (c) treated as (a) weighed 39 gr. (d) treated as (a) weighed 42 gr. * One ounce of whiting treated as (a) left 7 gr. From thefe experiments it appears, that the Four ounces of acid marked (a) contain as much acid of vitriol as will make 4 an oz. lefs 2 gr. of felenite. Four ounces of acid marked (b) 4 an oz. and 24 gr. of ditto. Four ounces of the acid vapour marked (c) 4 gr. of ditto. Four ounces of the acid vapour marked (d) none. Hence it is evident, that the vapour of the acid of fait condenfed in water, when diddled flow, contains no acid of vitriol ; and that even when it is diddled quick, it contains fo fmall a quantity as is not worth notice. * As whiting contains fome parts which arc not foluble in diftilled vinegar, it was necefl'ary to know how much of this an ounce contained, which muft be deducted in proportion to the quantity t.fed for the experiments a, b, c, and d. If [ 527 ] ^ 5.°^ sre diftilled in the common manner with an equal quantity of oil of vitriol un- mixed with water, there only diftil 2 ^ of fpirit of fait; whereas, if diddled in this new manner, we not only obtain the like quantity, but likewife 4 3 an half more, which are condenfed in the water; fo that in making this concentrated fpirit of fea fait, there is a having of above double the quantity, which would be loft in the common method of operating. Of the heat produced by the vapours of fpirit of fait palling through water, fpirits of wine, and oil of turpentine : Three quarts of water were put into a gallon ftone bottle, and made ufe of to condenfe the va- pouis, as in experiment the 2d, fig. F; in three hours and a half after the fire was made under the retort, the water in the ftone bottle had acquired the degree of 212, which is the mark of boiling water in Fahrenheit’s thermometer; and at this time there was fcarcely 2 3 of fpirit of fait diddled into the bottle, fig. C. The receiver and bottle C feemed cold to the touch ; the water at F had in- creafed 2 lb 3 Another like bottle with the fame quantity of water being put in the room of this, in fome time, acquired the fame degree of heat. The fumes feem to condenfe very well until the water acquired a heat within twelve degrees of boiling water. Spirit of wine rectified, made ufe of indead of water to condenfe the vapours, acquires a heat equal to 188 degrees; and it grows of a deep brown co- lour, though tranfparent. Oil [ 528 ] Oil of turpentine applied to the fame ufe ac- quires a heat of 12 degrees above that of boding water or 224. degrees ; it becomes of a dai k brown colour, though tranfparent, and has a difagreeable bituminous fmell. The thermometer not mea ur- ing more than 213 degrees, could not be left with fafety any longer. . , r nc Another time oil of turpentine was made to condenfe the vapours, which proceeded from 1 m of fal ammoniac, with i lb * of oil of v iti 1 , and 5 of a pound of water : here it did not giow near fo hot, nor fo high coloured, as in the other experiment, but was for the moft part congealed. PThe difference of thefe two experiments may perhaps, be owing to the fmallnefs of .the quan y of the ingredients in thelaft procefs; form the fi ll there was 1 4 lb of fait, 14ft of oil of vitriol, and 7 lb of water. Of the re-abforbtion of Air in DifliUations. In all diftillations a quantity of elaftic air is let free in the beginning, but afterwards there is a re- abforbtion of the fame ; the followmg experiment was made to fbew how great it is in fome cales. For the apparatus. Ice fig. 1. One pound and a half of foreign fal ammoniac was put into a retort, and itbt ° °'l of v.tuol (prevfoufly diluted the day before with ? oi a pound of water) 'poured on it, and a recipient well luted to it- the recipient had a tube 31 inches, well led and luted to it, and this tube was immeried m a glal's veflel containing a quart of water. The [ 5 39 ] The (pint of fait which was difilled, 1L weighed i The quart of water increase! in weight The caput mortuum weigh’d ' 2 The lofs in the operation was only 3 5 2 5 5 4 3 4 ■3 3 12 The operation was continued till the fal ammo- niac began to fublime. When no more air ©leaped, which might eaflv be perceived by its ceafmg to bubble through the water, the veiTel of water was taken away, and the tube was immerfed in a bafon of quick fiver; the mercury rofe in the tube 23 inches and a half, whilft the recipient was too hot to bear one’s hand on it longer than half a minute; when the recipient was quite cold, the mercury rofe to 29 inches and JL., and there was near one inch of fpirit of fait on its furface. This experiment was tried the nth of November, when the barometer was at 30 inches. In order to make this experiment fucceed, it is of the utmoft confequence to lute well the vefiels. On the Marine /Ether. The Marquis De Courtenveau, of the Royal Aca- demy of Sciences of Paris, has publiihed a very curious memoir in their Tranfadtions, on the mak- ing of Marine iEther, by diddling fpirit of wine with the * liquor fumans of Libavius ; but no one, that I know of, has fucceeded in making it with the pure fpirit of fait. It was natural to conclude * The liquor fumans is made by diftilling mercury fublimate with tin, and is compofed of the acid of fait united with tin. Vol. LVII. Y y y from [ 53° ] from the extreme great acidity of the fumes of fpirit of fait, that iEther might be made by faturating rectified fpirits of wine with them ; and on trial I found it anfwer, though not in a large quantity. The fpirit of wine, charged with the acid va- pours, mull: be diddled and cohahated, and then rectified with a flow degree of lire *. The method that Monf. Beaume of Paris pro- poled to make this iEther, and which did not luc- ceed with him on account of his not being able to condenfe the fumes, anfwered well with me; and it confifts of combining the vapours of fpirit of lalt with thofe of fpirit of wine. The apparatus that I made ufe of for this purpofe is defcribed at fig. 4, and the procefs is as follows: Eight pound of fea lalt was put into the retort B, and two quarts of rectified fpirit of wine into the retort D; three pints of the fame fpirits of wine were put into each of the glafs veflels I and K, in ‘order to condenfe the fumes, one not being fuffi- cient; all being well luted and fecured, the fpirits of wine in D were made to boil, and then yVa of oil of vitriol was poured on the lalt in the retort B, at ten or twelve different times, feven minutes be- tween each time, led the mixture (liquid boil over; then a fire was made under this retort, and both tires kept up till the operation was over. The quan- tity of liquor in the veffels I and K, increafes con- fiderably from the vapours that condenfe therein ; and the veffel I in particular grows very hot, and being * As 1 have fhewn before, that the vapours of the acid of fait, which condenfe in water, are free from the acid of ritiiol, vvt may be certain, that the acid of vitriol did not cor.tiioutc to form this /Ether. [ S31 ] highly charged with vapour is rendered incapable of condenfing any more; the vapours then pais on to the veffel K, and heat that alio. The liquor then that was diflilled into the veffel F, was mixed with the liquor of the veffels I and K, then being * diddled, cohabated and rectified flowly with flacked lime, produced a very fubtile penetrating fEther; it is very remarkable, that this, though free from acid, upon mixing it with water, caufed a violent ebullition. An expeditious method of making Nitrous /Ether by Diftillation, without Fire. (See fig. 5.) Pour flx ounces of the molt concen- trated fpirit of nitre, little by little, on eight ounces of rectified fpirit of wine, (baking the veffel each time in which the mixture is made. Then convey it by a long funnel through the opening of the head at C, into the matrafs A ; the opening is afterwards lecured by a glafs flopper ; in warm weather this mixture grows hot in five or fix minutes, and diftills in a ftream into the veffel E, and is over in about half an hour. Before the ma- trafs grows cold, a frefh mixture is put in as above, and fo on for five or fix times, till there is liquor enough diflilled. This liquor being flowly re&ified * Spirits of wine was ufed likewife here to condenfe the va- pours ; and though the diftillation was condu&ed with a very flow fire, yet theVpirits of wine grew very hot. Spirit of wine was likewife ufed to condenfe the vapours in the cohabation, but thev did not grow hot. This liquor without cohabation affords iTther, but not fo great a quiimity- Y y y 2 with C 532 1 with flacked lime, makes very fine /Ether. The fpirit of wine, which was put into the vefiels E and F to condenfe the vapours, is fio highly charged with /Ether, that it will feparate on wafhing with water. This fpirit of wine is alfo an exceeding rich fpiritus nitri dulcis. What remains in the matrafs contains a quantity of fpirits of wine, which may be feparated by di- ftillation. On the Diftillation of the Nitrous Acid, fee fig. 2. The quantity that is condenfed in water dur- ing the diftillation of this acid fpirit is fo fmall, that it would be fcarce worth having, if it was not to prevent thofe noxious fumes, which have fuch an effedt on the lungs of the operator, as frequently to make him fpit blood. Water highly charged with thefe fumes by re- peated diftillations becomes blue, and retains its colour *. I once diftilled, in an iron body with a ftone head, 30 lb of nitre, with 60 'lb of green vitriol, which I had calcined to whitenefs, and was obliged to make ufe of two vefiels of water, as in fig. 5, at F and G, to condenfe the vapours: this water became * Oil of vitriol was ufed in this operation, to fet free the acid of nitre ; and I found upon trial the fumes condenfed in the wa- ter to be a pure fpirit of nitre : whereas, ia the other operation, where calcined vitriol or copperas was ufed, the fumes contained fome acid of fait. This led me to try the common green coppe- ras, and I found it contained a por:io,i of iron united to the acid of fait : whereas the Dant&iclc copperas or vitriol contains no acid of fair, and therefore is fitter to make an arjua fortis for the refiners ufe. . . [ 533 ] blue in one di&illation, and continued fo for 18 months, till I made ufe of it. _ -A great quantity of air was fet free from the be- ginning to the end of the diftillation, owing in a great mealure to the acid fumes aiding on the iron Dody ; for it diddled in a glafs or (lone vetlel, the quantity of air is not near fo confiderable. The nitrous fumes condenfed in water, in mak- ing the ipiritus nitri fortis appear to be more acid than the dronged oil of vitriol made ufe of for the experiments on fpirit of fait. Water is not heated by thefe fumes, owing pro- bably to the fmalleft of the quantity which con- denfes therein. A further application of this new method of Di- fl illation . In the diddlation of the oil of vitriol, a great part of the acid comes over fulphureous, and is very hard to condenfe ; but, by pafling it through water, this condenfation is eafily obtained : however, a greater quantity of water is neceffary for this operation than for the fpirit of fait, though the water be- comes but flightly acid, yet it is greatly fulphu- reous, and at the fame time acquires no heat. The fulphureous acid obtained by other means, as by diddling the acid of vitriol with mercury, and other fubdances, is likewife condenfible. Further, this fulphureous acid of vitriol may, by two or three flow rectifications, be deprived of its acid j but it will dill retain its penetrating fulphu- reous gas-like fmell. The t 53+ ] The v j pours which arife in the deflagration of nitre, with charcoal, antimony, &c. commonly c ailed Ov'flus, are very bard to condenfe; hut, by making them pafs through water, tneir condenia- tion is thoroughly efteded. See lag. 6. In the reification ot Phofphorus, if water is made ufe of to condenfe the vapours, it will be- come as white as virgin wax, and almoft as pliable; which fee ms to be owing to the water, whicn pre- vents its burning. In the diftillation and redification of the Vitriolic if' the r, it is of advantage to make ufe of fpirit of wine to condenfe the vapours, which otherWife might have been diffipated. Befides thefe, a great many other things, too te- dious to mention, may be condented in water, or fpirit of wine, to a very great advantage. I cannot conclude, without mentioning that this new method of diftillation bids fair to difcovei the mercurial and colouring eartns ot Beecher ; for by this method we can condenfe the moil volatile parts of all fubftances, far better than by any other means. . And I muft acknowledge that I received the nrit hint of it from the common apparatus for reviving mercury from cinnabar. I am, fir. Your mod obedient fervant, Cleikenwell, Nov. 18, 1767. Peter Woulfe. To John Ellis, Efq; in Gray’s Inn. Ex pi a- [ III ] ^ ai&n Jo noijfiiulqx; -l siusil Phi/MTm„i.VoL7.VII. TAtt-Jncr.fi. $35. •13>*W fill"; IsTbv -jnofl .mojjod orli „ looql , art 1 iliftib rl^l'^■/r -joupil 5/J] WoqJs ?i oajfj u,,, . .... tlini ni i. ■ ' ; . odu qofi uj fjjloa H IL jl; , ■St*/. 2. J 3 C,nltje C 535 ] Explanation of Plate XXV. Figure i. A, A glafs retort. B, A glafs receiver. C, A bottle to receive what didils. F, A glafs, or ftone veflel with water. The recipient B, has a fpout at the bottom, which conveys the liquor which didils into the bottle C ; at the end there is a fpout D. E, A crooked glafs tube and i_ of an inch bore. G, A cork with a femicircular notch to hop the bottle F. Figure 2. A, A gl afs retort. B, A glafs receiver. C, A bottle to receive the diddled liquor. H H, Glafs or ftone vefiels, with glafs {toppers, ground and fitted to L L. F, A done bottle with water. D, A crooked tube, as at E, fig. i. I, Another crooked tube. K, A cork, with two femicircular notches to fit the crooked tubes to the veflel H. Figure 3. A, An iron body with a done head, which has a dopper at b. B, A dand to fupport the receivers and bottles. Figure 4. A, The furnace, in which is placed the retort B. 2 A [ 536 ] D, A glafs tubulated retort, which is to be coated with loam up to B. C, Another furnace. D, A tubulated retort, fixed in a veflel with fand. I'h A {fone vefiel, wherein the vapours of B and D are combined together. F, A ^bottle to receive the liquor which difiils. A iarge tube fitted to E, about JL inch bore. H, A crooked pipe about JL inch bore, f and K, glafs vefiels containing Ipirits of wine. L, A crooked glafs tube. Plate XXVI. Figure 5. A, A glafs matrafs about 4 7 feet high. B, A glafs head, with a fpout and glafs ftopper C. H, A glafs tube. P, The receiver. E, The bottle to receive the liquor which difiils. F and G, Glafs vefiels containing fpirits of wdne. PI IP, crooked tubes. Figure 6. 0 A, An iron or earthen retort. B, The upper part of the retort, with an opening at top, which is to be Hopped occafionally. CCCC, Crooked fione pipes. DDDD, Glafs receivers, containing water. E, A crooked fpout, proceeding from the lafi re- ceivers, to let out the air that is fet free in the operation. INDEX. V' Philos.Tmrur. %iLVJl. Y/I/iJOCYT. p. 53 6. ,T Jc • ' ' . Vi * . t. A N INDEX TO THE / Fifty-Seventh VOLUME OF THE Philofophical ’Tranfa&ions. For the Year 1767* A. A BDULy Roobin, a Sooloo pilot, his obfervation about zl the iQands on the N. E. coaft of Borneo, p.394. Uieful to navigators, 397. Accelerators urina , voluntary in expelling the urine, involuntary in expelling the femen, p. 128. How this phenomenon is accounted for, 129. Acid of fea fait, made ftronger than oil of vitriol, p. 525. Acids do not promote the folution of Bark, p. 230. De- Itroy aftringency, 231. Thought to amount to no more than four, 480, reduced to one by fome chemifts, p. 482. Acids , vegetable, whether they are all the fame,, p. 479. Aftinia. or animal flower, p. 428- Its defeription, 429. Z z z Amnia , 53s INDEX. /Sinla Socfata, or 'cluttered animal flower defcribed, p. 431. Is an animal compounded of many animals, conne&ed to one common root, 433. Difcovers its mufcles, tendons, and flomach, 435. Aether, marine, prepared by the method of Mr. Beau me, p. 530. Nitrous, made without fire, 531. Air , Jet free in the beginning of distillation, and re-ab- forbed afterwards, p. 528. Air , fixed, contained in Rathbone place water, p. 97 — 99. Alexander , Mr. Experiments with Camphire, on himfelf, p. 65. - • Alkaline i hits, are three, p. 480. Alkalies , volatile, their diftillation improved, p. 519, 520. Amber, Succinum, its acid thought the fame with that of fea fait, or of vitriol, p. 509, 510. Proved different by Dr. Stockar, 510, 51 1 ; and by Dr. Monro, ibid, generates cold with volatile alkali, 512. Andrachne , a fhrub raifed from feeds, fent by Dr. Ruffe) l from Aleppo, in 1754, p. 1 1 7. Produced flowers for the firft time, in the garden of Dr. John Foihergill, 1 15 -y defcribed by Mr. Ehret, ibid. Animal flower (fee Adlinia ), their pretended flowers are mouths, 435. Animals, found in countries about the Volga, p. 341. Animals , large, whole bones are found in North America, probably elephants, of a fpecies hitherto unknown, p. 468. Antiparos, grotto in that Eland, where cryflals and fpars are formed, p. 6c. Apparatus , new, for electricity, p. 168. For condenfing of vapours in diftillation, 518. Apple, its acid juice, p. 489. Neutral fait formed with it, and the foflil alkali, 490. Arch, luminous, feen at Oxford, by the Rev. Mr. Swinton, p. 109. Aimojphere, of the fun, extends at lead to of its dia- meter, p. 152, 153; thought to be much higher from the height of its fpots, 400, 401. Atmofphcre , INDEX. 539 Atmofphere , of Venus, one third ofirs diameter, p. 401. Aurea , Cherfonefus, the fame with Malacca, p. 155. Attraction , its limits, between the Sun and Comets, P- *33- B. Baal, Tars, equivalent to Jupiter Tarfenfis, p. 269. Bacchus , worfhipped at Tarfus, p. 270. Bark , Peruvian, infufion ot it preferable to Decodtion, p. 221 — 227 ; efpecially when made in cold water, 228 : contains both the gummy and refmous part, ibid. Tindture of it has the fame advantage, ibid. Its folution weakened by quick-lime, 232. Its extradt, a very weak preparation, 229. Barrington, Hon. Daines, on particular Fifh found in Wales, p. 204. Bajler , Dr. Job, afierts that the Corallines are plants of the genus of the Confervas, p. 404. Bath Waters, their heat, p. 202, 203. Beccaria , Joannes Baptifta, his new experiments on eledtri- city, p. 297. Bengali , uncommon heats of the climate, p. 218. Its unhealthinefs, 219. Benzoin, its acid afcertained, p. 507. Generates cold with the volatile alkali, 509. Bevis, Dr. John, fir ft difcovered, in 1761, a fource of irregularity in the durations of the eclipfes of Jupiter’s Satellites, from the prolate fpheroidical figure of that planet, p. 28. His tranftation of a memoir of Mr. Mallet, on water- v/heels, p. 372. Birds , found about the Volga, p. 346. Bourdelin , Mr. thought that the acid of amber was the fame with the lpirit of fea fait, p. 509. Approved by Macquer, 510. Both miftaken, ibid. Bradley , his account of the fecundity of fifh, p. 2 So, 2S1. Brainlefs Z z z 2 $4° INDEX. Brainlefs fcetufes are very lively, p. 17. And why ? 18. Brijlol Stones, grow within the cavity of rough {tones* and have different appearances, p. 59.. Of different fizes, and why ? 62. Brijlol Waters, their hear, 202, 203. Buffaloes lick , in North America, why fo called, p. 464, 5, Burnet, His account of the Deluge, p. 45. Oppofed by Dr. Kei 11, ibid. Defeats in his hypothecs, ibid. Byron , the Hon. Commodore, was among the Pata- gonians, p. 77, 78.. Their fize compared with his, 78. C. Calcareous cruft, always produced from an animal, p. 415. 422 . Calcareous earth, kept fufpended in moft waters, p. 92. By being united to an over-proportion of fixed air, 101. 103. Or by being intirely deprived of it, ibid. Pre- cipitated by the addition of lime-water, 107. Cambodia , the Sina ol Ptolemy, p. 1 6-3. Was the metro- polis of the ancient Sinte, 165. Camp hire, taken to the quantity of Di, funk the pulfe three degrees, p. 66. Dii increafed by degrees the pulfe from 77 to 100, 68. Brought on heat, delirium, fick- nefs, and lofs of memory, 69, 70. Canton , Mr. John, on the heat of the Bath and Briftol waters, p. 203. Carp , number of their eggq p. 086. Cattigara , the fame with Pon tea mala on the Bay of Siam* p. 164. Cavendiffy the Hon. Henry, h-is experiments on Rathbone- place water, p. 92. Caver hill, Mr. John, attempts to afeertain the knowledge ^ of the ancients in the Eaft Indies, p. 15^. Cdlularias, fpecies of Corallines or cluttered animals, P* 43 4* C banning, Mr. his defeription of three fubftances, mentioned by the Arabian phylicians, p. 21. Chclfca I N D E X. ^ Cbelfea plants. See Hudfon. Circulation of the blood from the mother to the foetus* and from the foetus to the mother, proved , from the confideration of a monftrous child, p. 16, 17. Clarke , Mr. his account of tall men feen near the Streights of Magellan, p. 75. Clujlers , of ftars probably belong to the fame fyftem, 249. Cod , contains feveral millions of eggs, p. 287. Cold , greateft in London, p. 445. Norwich, 444. Ply- mouth, ibid. Derby, 265. Cold , or heat, what degree produced by acids mixed with alkalies, p. 514. Collinfon , Peter, F. R. S. his account of foffil teeth found in North America, p. 464. 468. Comet , of 1665, three times and a half denfer than the earth, p. 148. of 1672, as 11 to 5, 149. Comets , a method of inved.igating their denfity, by means of the height of their tails, p. 146. Probably denfer as they approach nearer to the fun, 150. Communication of the umbilical vein with the aorta, in- ferior in a monfter fufpected, by Mr. Le Cat, p. 14, Confervas , what plants they are, p. 421. Some of them of the ciafs of Dioecia, 424. Several beautiful fpecies of them, ibid. Cook, Mr. James, his obfervation of an eclipfe of the fun, at Newfoundland, p. 215. Coral Banks, raifed by the winds, form into fhoals, p. 39.;. Become a bar to coagulate the fand, ibid. And being enriched by the dung of birds and cafl-up vegetables, are covered with mould, and become iflands, 396. Corallines , when burnt, have the i'mell of burnt bones, p. 410. Give by diftillation volatile alkali, falts, and oils, 41 1. Corallines , whether their pores are too minute for polypes* p. 413. One of them laid to be found on a heath, 415. By mittake, whether they contain feeds, 41^ Craby the mod prolific of fhell fifh, p. 288. Croohm*, t un- 542 INDEX. Qroghan , George, Efq; difcovered the bones of fome known animal in North America, p. 464, 465. Cryjialhne particles, carried by moifture, coileft in drops, and form into maffes, p. 60. More or lefs tranfparenr, in proportion as they are drawn clofe together, and free from heterogeneous matter, 61, They are probably a kind of falcs, 62. Cryjiallifation , different methods produce a varietv in the figures of the falts, p. 496. Ciyjlals , and lpars formed in caverns, where moifture ^ defcends through the earth to a void fpace, p. 60. Cylinder of g:afs, lined for electrical experiments, becomes much more powerful, p. 186. D. Dalrymple , Alexander, on the formation of'iflands, p. 394. Deluge , univerfal, how accounted for by Burner, Whifton, and Ray, p. 45, 46. And by Mr. King, 48. Derby , cold at this place fuperior to that' of any place in England, p. 265. Diamonds, why large ones are fo rarely found, p. 64. Diofcorides, an Arabic MS. of this author in the Bodleian Library, p. 22. Dijlillaticn of acids, volatile alkalies, &c. how improved, P-517- E. Eclipfe of any of the Satellites of Jupiter determined, P* 37- Eclipfe of the Sun, of Auguft 5, 1766, obferved at New- foundland, by Mr. Cook, p. 215. At Oxford, by the Rev Mr. Hornfby, 216. Of AuguJt 16, 1765, at Caen, by N. Pigott, Efq; 402. Eggs, their number, in feveral fi flies, how afcertained, p. 282. Table of them, 291, 292. Ehrct , INDEX. 54. Ehret , Mr. G. D. his defcription of the Andrachne, p.i 14. Electrical machine contrived by Mr. Read, p. 451, 452. Electric fluid, palling through water, p. 459. Electricity, its effeds in a cafe of the locked jaw, p. 89, 90. How to be increafed, 186, 187. How preferved, 188. New experiments on eledricity, by Father Beccaria, 297. Electrometer , by Mr. L’Epinaffe, p. 191. By Mr. Lane, 452. Its principle, 453. Itsufes, 454, 455, &c. Ellipfis for dials, how defcribed geometrically, p. 392. Ellis, John, Efq-, on the animal nature of Corallines, p. 404, Elis difcoveries on the Confervas, 424. His account of the Adinia Sociata, or Cluttered animal flower, 428. Equation , hypermechanical, what, p. 359. Refolved by means of a curve, 360. Etna, in Sicily, its eruption in 1766, p. 198. F. Fantoni , Pius, of Bologna, his evolution of a mecha- nical curve, p. 358. Fergufon, Mr. James, his new method of conttruding fun- dials, p. 389. Fevers, malignant, called Pulker at Bengali, p. 219. Fires, fubterraneous, undermine the whole furface of the earth, p. 46, 47. Thofe which produce the whireft light are the brighteft, 238. Fijhes , different accounts of their fecundity, p. 280, 28 r. How it may be afctrtained, 282. Of the river Volga, 355. Fijh, monocular, Arid by Giraldus Cambrenfis, to be found in the lakes of Snowden, p. 207. His account con- firmed, 209. Found in a lake in France by Mr. Monta- lembert, 210, 2 1 1. Fleming , Martin, Efq; on the heat of Bengali, p. 21 8. 2 Float- 54* INDEX. Float -boards, parts of water- wheels, p. 372. Their fize, how determined, 3 73 — 375. Their velocity, 376— 380. Their number, 381 — 387. Flounder , had above a million of eggs, p. 287. Forjter , J. R. his Elfay on the natural hiltory of the Vol^a, p. 3 1 2 • Frafturcd legs, what is to be done immediately, upon an accident of that kind, p. 84. Fucufes , true plants, analogous to the Confervas, p, 426. Fumes. See Vapours. G. Ganglions , on the nerves, feem intended to intercept the power of the mind ov£r them, p.120—131. Objections to this hypothefis anfwered, 121, &c. Feelings of nerves come from ganglions bluntand confufed, 125. Giraldus Cambrenfis, his character, p. 207. What he fays of fome fifh with one eye, in the lakes of Snowden in Wales, 208. Glafs, broke, by means of electricity, p. 459. Green glafs, more difficultly than white, ibid. Grinders , of large animals, brought over from North America, 465. Different from thofe of the elephant, 468. Gwyniad, Filh of that name whether peculiar to the Lake Bala in Merionethfhire, p. 21 1, 212. H. ’■'* t Hamilton , the Hon. William, on the eruption of Mount Vefuvius, of 1766, p. 192, &c. Paffed feveral nights on the mountain during its erruption, 194, 195, 196. Farmer, M. Thomas, on the fecundity of fifties, p. 280. Heberden, Dr. 1 homas, on the increafe and mortality of the inhabitants of Madeira, p. 461. Herrings , the number of their eggs, p. 284. Honey, its acid, p. 505.-507. P Horjlcy , INDEX. 545 Horjley , Rev. Mr. S. his computation of the fun’s di (lance from the earth, p. 179. Attempt to determine the height of the fun’s atmofphere from the height of its fpots above its furface, p. 398. Howard , John, Efquire, on the heat of the waters at Bath, p. 201. Hudfon , Mr. William, his account of the Fifty Chelfea Plants, for 1766, p. 407. 0 Hydra , or fiefh water Polype, defcribed, p. 430. Hydrocephalus , often the origin of brainlels monflers., p. 19. Hydro-enterocelej defcribed by Mr. Le Cat, p. 293. Mifta- ken for an Hydro-farcocele, ibid. I. Java, known by the ancients under the name of Jabadiu* p. 170; but only in part, 172. lnfedl, found in a ditch, defcribed by Mr. King, p. 72. hjlrument for fractured legs, invented by Mr. Sharp, p. 80—87. Defcription of it, 82, 83. Its advantages, 85, 86. Serviceable to broken thighs, 87. Irfiruments may be conflrn&cd capable of diftinguifhing the 20th part of a fecond, p. 239. JohnJlon , Dr. James, Hiftory of a foetus born with a very imperfect brain, p. 118, His thoughts on the ufe of the ganglions, p. 120. JJlands raifed by fubterraneous fires, p. 47. Formed by coral-banks, 395. Mud be long and narrow, 396. Jupiter , its prolate fpheroidical figure aff'eds the duration of the eclipfes of its fatellites, 28. Error arifing hence, 4 3’ JaJlamond , Mr. J. O. His tranflation of a memoir of Mr. Le Cat, p. 293. K. King, Mr. Edward, his Attempt to account for the uni- verfal deluge, p. 44. He fuppofes that what is now 4 A fea 446 INDEX. lea was formerly dry land ; and what was the bottom of the ocean formerly was raifed to be dry land, 48. His reafons for thinking fo, 50. Objections to his hyporhefis folved, 50, 51. Attempt to account for the formation of fpars and cryftals, 58. Defcription of an aquatick infeCt, 72. L. Lane , Mr. his defcription of an electrometer of his in- vention, p.451. Experiments made with it, 456. Lava, from Mount Vefuvius , ran near a mile in an hour’s time, p. 194. Appears like red hot and liquid metal, ibid. Refills the imprelfions of ftones thrown on it, 196. Le Cat, Mr. his account of a monftrous human foetus, p. 1. Account of an Hydro-enterocele, 293. VEpinaJfe, Mr. his Defcription of an improved apparatus for eleCtrical experiments, p. 186. Lezvenhoek found above nine millions of eggs in a cod- fifh, p. 280 — 287. Light from the Sun compared with that of Saturn, p. 235. Lightning, its effeCt on buildings imitated by eleCtricity, 456, 457. Whether lefs mifchievous after a Ihower of rain, 457. Lion tearing a bull, a fymbol of Parthian medals, p. 274. Linnaeus. His opinion about corallines, p.404. About calcareous crufts, 422. Lobflers , their fruitfulnefs, p.288. M. Mackarel , their fecundity greater than that of carp, p. 285. Madeira, number of its inhabitants, p. 461. Their in- creafe, chriftnings, weddings, and burials, 462. Mor- tality of the feafons, 463. Magnefia contained in Rathbone-place water, p. 93. Mallet , I N D E X. J47 Mallet , Mr. of Geneva, his memoir on water-wheels, p.372, Mamiraam , a fpecies of the Chelidonium, p. 23. Mzw milk fermented, called Kumys by the Khalmucs, P- 34^* Mamitha , or Mamithfa, the Glaucium of Diofcorides, an Papaver corniculatum floribus coeruleis ? p. 24, 25. Memory loft in a Arrange manner from a large quantity of camphire, p. 68, 69. Minerals found in the countries about the Volga, p. 3 15, &c. Michell , Rev. John, his inquiry into the parallax and magnitude of fixed ftars, p. 234. Has fhewn that fub- terraneous fires are liable to make eruptions under the fea, 48. Moijlure carries along with it cryftalline falts, p. 60. When the flow is quick, the cryftals are large, but lefs perfect, p. 63. Monkeys great and mifchievous in 'the Celebes Iflands, p. 1 7 1 . Monro , Dr. Donald, his account of neutral falts made with vegetable acids, fhewing that thefe acids differ from one another, p. 479. Montagu , Edward Wortley, Efquire, on what is called Pompey’s Pillar, p. 438. His difcoveries in it, p. 439. Monftrofity caufed by a dropfy or hydrocephalus, p. 19. Monftrous foetus defcribed by Mr. Le Cat, p. 1. Another brainlefs foetus defcribed by Dr. Johnfton, 1 18. Montalambert , his curious obfervation of fome monocular fifh, p. 210. Moon's denfity greater by 4 than that of the earth, p. 185. Moon's mean diftance from the earth found by Mr. Horfley to agree with Sir Ifaac Newton’s determination, p. 185. Moro Lazar 0, a Venetian author, afferts that the conti- nents were originally raifed by fubterraneous fires, P- 57’ 4 A 2 Narborougb, 548 index. N Narborough , Sir John, his account of Patagonia con- firmed, p. 79. Neutral falts, their number reduced to twelve, by Dr. Cullen, is in fa£t infinitely greater, p. 513. How they might be divided, 515. Newfoundland , its longitude, 215, 216. Nitrous fume condenfed, p. 532. More acid than the firongcft oil of vitriol, 533. Nitrous falts abound in molt of the London waters, p. 94. None found in thofe of Rathbone-place, ibid. O. Ohio, fomi bones found near the banks of that river, p. 465. Okeyhole in Somerfetfhire, p. 60. Orchell , true, is the Lichen Roccella Linnaei, p. 409. How diftinguifhed from a Coralline, 410. Or°d , or Vorod, a Parthian King, p. 276. P. Pallas, Dr. decides that Corallines are not Zoophytes, p. 405. Parallax of the brighteft fixed ftar, lefs than two feconds, P* 235> 236* Of the fun computed by Mr. Horflev* p. 184, 185. Parthian Kings wore long breeches, reaching down to their ancles, p. 273. Parthians , medal (truck by them of their victories over the Romans, 275. Patagonia , hilly, fandy, and without trees, p. 79. Patagonians feen by Commodore Byron in 1764, p. 75. Their fize, 76. Peak, in Derby (hire, cry ftals found there, p. 60. Perch , INDEX. 549 Perch , crooked, found in a pool of Merioneth (hire, p. 504. Perch lefs prolific than tench, 286. Percival, Dr. Thomas, his experiments on the Peruvian Bark, p. 221. Perry , its acid, p. 503. Petit, Dr. found above three hundred thoufand eggs in a carp, p. 280. Phoenician medal, in the Earl of Morton’s collection, ex- plained by Mr. Swinton, p. 265. Probably ftruck at Tarfus, 269, 271, when the Parthians were mafte'rs of Cilicia, 274. Phosphorus , how beft rectified, p. 534. Pigott , Nathanael, Efquire, his observations of the fun’s eclipfe, Auguft 16, 1765, at Caen, p. 402. Pine tree, appearance of it on Mount Vefuvius, defcribed by Pliny, as a forerunner of an eruption, p. 194. Plants found about the Volga, p. 323, &c. Pleiades , appear to be a fyftem of ftars by themfelves, p. 251. Plymouth , meteorological diary of 1767 there, p. 446 — 4 50. Pompefs Pillar, in Egypt, defcribed, p. 438. Its di- menfions, 439* Made of granite, 440, Rafted on a reverfed obelifk, covered with hieroglyphics, ibid. Probably ere&ed at the time, and to the honour, of Vefpafian, 441. Pontemafs. See Cattigara. Probability of any two or more ftars of the fame magni- tude, being within a certain diftance of one another, p. 243, &c. Ptolemy , his account of the navigation of the ancients in the Eaft Indies, p, 156. Quick-lime , neither quickens nor increafes the folubility of bark, p. 232. „ , . Rathbone - 55° INDEX. R. Rathbone-place water, examined by the Hon. Henry Ca- vendifh, p. 93. Grows cloudy upon dropping a fo- lution of corrofive fublimate, ibid. Its contents by diftillation, 93, 94. Diftilled, contains a volatile al- kali, 95, 96. Ray\ his account of the deluge unfatisfa&ory, p. 4 6. Reptiles about the Volga, p. 351. Romana Cape, the moft fouthern point of land in Afia, p. 158. S. Salt) common, extradited from Lake Yelton in very great quantities, p. 320. Salts and fulphurs difcharged from Mount Vefuvius, p. 199. Salts neutral, formed with fermented vegetable acids and the foil'll alkali, p. 498, With diftilled vegetable acids, and the foftll alkali, 504. With flowers of benzoin and fait of amber, 507. Satyrs, Hands of, were probably the Celebes, Borneo, &c. p. 1 71. Senfibility may exift without the brain, p. 18. Seres, their country part of Thibet, p. 163. Sertularias , from a creeping adhering tube, fend up feve- ral branched animals, p. 434. Sharp , Mr. Samuel, his account of a new inftrument for fractured legs, p. 80. Made the ftrft with his own hand, 87. Shells, found in all parts of the prefent continents and Hands, p. 47. Their beds confift generally of one or two different forts in particular places, 57. Serica, ancient, where, p. 163. Shrimps , INDEX. 55i Shrimp, very prolific, in comparifon to their bignefs p. 288. ° 5 Since , ancient, their fituation, p. 161, &c. Sirius , its parallax probably of one fecond, p. 241. Smelts have a vaft number of eggs, p. 285. Soal not fo prolific as flounders, p. 288. Solar fpots are much higher in proportion than our clouds, p. 400. Solfa- terra, its fulphurs and falts different from thofe of Mount Vefuvius, p.200. Spars and cryftals formed in flints, and other bodies for- merly in a foft date, p. 59. Spars differ from cryftals from a fmall mixture of hete- rogeneous parts, 61. Spry, Dr. Edward, his account of a locked jaw, and para- lyfis cured by electricity, p. 88. Stars, their want of an obfervable parallax owing to their diftance, p. 234. Difpofed into groupes, probably be- long to the fame fyftems, 243 — 249. Single ftars may belong to our fyftem, p. 252. Steward , Dr. his computation of the parallax of the fun, p. 179. Agrees with Mr. Horfley’s, p. 184: Stones red hot fhot, from Mount Vefuvius, to the height of 200 feet, p. 195. Sumatra , known to the ancients only in part, p. 172. Sun, to what fyftem of ftars he belongs, p. 251. Proba- bly ranks only with the ftars of the fourth magnitude, P- 255* Sun-dials, how conftru&ed without dialing fcales or lo- garithmic computations, p. 389. Sun’s parallax 6", 52"', 415, p. 181. Swinton, Rev. John, his defcription of a meteor feen at Oxford, October 12, 1766, p. 108. Obfervations on fwarms of gnats feen at the fame place, 111. Inter- pretation of a Phoenician medal, 266. T tbajheer. 552 INDEX. T. Tabajheer, a fubftance found in the cavity of Indian canes, p. 24. Tails of Comets, confid of very volatile particles, p. 153. Doubts about their ufes, 153, 154. Tar [us, wine was made in the diftiid of that City, p. 263. Tench, more prolific than carp, p. 286. Thina. See Sin#. Tr anfparency of bodies, occafioned by the minutenefs of their pores, p. 60. Trituration , very ufeful to promote the folution of Peru- vian bark, p. 229. Trout , crooked, in a river of Cardiganfhire, p. 204, 205. ■ Tujks of large animals, brought over from North America, p. 465. Are of fine ivory, ibid. Agree with the foffil elephants teeth, found in Siberia, 466. And with thole of Africa, 468. Twinkling of fixed ffars, occafioned by the inequality in the denfity of rays, coming from them in fmall portions of time, p. 262. V. Vapours , which efcape in common diftillation, how they may be condenfed, p. 518. Vegetable acids, their different affinities with alkaline falts, P* 51 4* Juices, how to be treated, in order to extract their acids, 515. - Venus , probably furrounded with an atmofphere, p. 240. 398. Next tranfit recommended to the confideration of all aftronomers, 183. Vefpafian , a medal of this emperor found, jn what is called Pompey’s pillar, p. 441. Vesuvius, its eruption in 1766, p. 194, &c. Vinegar, its acid,p. 499. 4 Underwood, INDEX. 553 Underwood , Mr. Michael, his tranflation of a memoir of Mr. Le Car, p. i. Volga , country about that river defcribed, p. 204. The two banks very different, 313. Very cold in the winter, excelTively hot in fummer, 314. Few ftones found there, 317. Uvea , its motions, whether involuntary or voluntary in all cafes, p. 129, 130. W. Wales , fingular fifh found there, 204; Watfon , Dr. William, on the cold weather of 1767, P* 443* Weljh mountains not fufficiently known, p. 213. Will ("power of the) on human life wifely confined, p. 13 1. Wintbrop , profeffor, thoughts on comets, p. 132. Witchell , on the curve formed by the fhadow of a prolate fpheroid, upon a plane perpendicular to the axis of the fhadow, p. 28. Whijlon , his account of the deluge defective, p. 46. White , Dr. his account of the caufe of fympathy, p. 127. Wbitehurji , Mr. John, his thermometrical obfervations at Derby, p. 265. Woulfe , Mr. Peter, his analyfis of corallines, p. 411. Experiments on the diftillation ot acids, volatile alka- lies, &c. 517. Y. Telton , Lake, fupplies Ruffia with fait, p. 318. Z. Zaba, food on the bay of Siam, p. 15S. Zoophytes , are true animals, p. 435. The End of the Eifty-feventh Volume. ERRATA Vol. LVI. P. 6. 1.8. for mvrmvris SONI, read mvrmvris, sonIj P. 301. note (9) 1. i.for Abulfed, read Abu’lfeda, P. 301. note (9) 1. i.for Firuz, read Firuz Vol. LVII. P. 113. 1. 4 .for Wadham College read Wadham College, P. 108. 1. 13 for 1766. read 1765. P 27 e. 1. 10. for Mount read mount P. 458. 1. 24. after the word determined infen a colon 4 BOOKS printed for and fold by L. Davis and C. R e y M e r s, in Holborn, Printers to the Royal Society. I. AN Abridgement of the Philofophical TranfaCtions, from the Inflitution of the Royal Society in 1665 to the Year 1750; by Lowthorp, Jones, Eames, and Martyn, in 12 vol. bell Edition. 2. The Philofophical TranfaCtions at Large; from the Year 1750 to 1 767, in 15 vol. which continue and compleat the above Abridgement to the prefent Time. In all 27 Volumes in Quarto. N. B. A very few Setts of this Work can be compleated. Thole who have not made up their Setts may he fupplied with odd Vo- lumes by the above Bookfellers. 3. The Hiltory of the Royal Society of London, for improving of Natural Knowledge, from its firit Rife : Being a Supplement to the Phi- lofophical TranfaCtions. In which the moll confiderable of thofe Papers and curious Experiments, communicated to the Society, when the Philo- fophical TranfaCtions were not regularly carried on, are inferted in their proper Order, and now fir ft publilhed : Together with a Ihort Account of the Lives of the molt eminent Members fubjoined. By Thomas Birch, D. D. Secretary to the Royal Society. 4 vol. 4to. illulirated with Plates and Figures,' originally fold for 3 1. bound, now at 1 1. 1 1 s. 6d. in Sheets. N. B. The Third and Fourth Volumes may be had feparate. 5£f= Extract from the Preface of the French Tranllation of the Philofo- phical TranfaCtions, by Dr. Demours ; Printed at Paris, 1759, 4to. “ We fee with Pleafure, in reading Dr. Birch’s Hillory of the Royal So- “ ciety, the immenfe Labours undertaken with Succefs by that Society, « in order for the Advancement of the Sciences. Their Enquiries “ firjl extended to every Thing that could contribute to the Progrefs of “ Natural Philofophy in general or particular. Mathematics, and the tt Arts, Natural Hillory and Botany, Anatomy, Chemiltry, Phyfic, “ Geometry, Mechanics, Hydraulics, Algebra, Optics, Aitronomy, « Geography, Hillory, Chronology, Antiquity, &c. In the Regiliers a 0f t]ie Royal Society are to be found many large and curious Dif- a courfes upon different Subjects, which had never been printed in the a philofophical TranfaCtions, and which deferved a Place in them. Dr. *t Birch’s Hillory, which is a faithful Copy of thole Regiliers, will fut'- it njfh Materials for rendering this Tranllation more interelling than the “ Originals themfelves.” 4. A Collection of the Yearly Bills of Mortality, from 1657 to 1738 inclufive. Together with feveral other Bills of an earlier Date. As a Specimen of the Ufe which may be made of them, there are fubjoined to this Collection : I. Natural and Political Obfervations on the Bills of Mortality, by Capt. John Graunt, F. R. S. 2. Sir William Petty’s Effay on Political Arithmetic, concerning the Growth of the City of London; with the Meal'ures, Periods, Caufes, and Confequences there- of* ". Obfervations on the pail Growth and prefent State of the City 3 ‘ of. BOOKS printed for L. Davis and C. Reymers. of London, in 1757. By Corbyn Morris, Efq; F. R. S. 4. A Com- parative View or the Difeafes and Ages, and a Table of the Probabili- ties of Life, for the lall Thirty Years. By James Fortieth way te, Efq; F. R. S. 4to. price ior. 6d. 5. Bibliotheca Literaria : A Colle&ion of Infcriptions, Medals, and Small Trades, Critical Dirtertations, &c. communicated by Mr. Wafle of Aynho, and other learned Perfons. 4to. Price 6 s. 6. s’Gravefande’s Mathematical Elements of Natural Philofophy, by Dr. Defaguliers, 6th Edit, with 1 27 Copper-plates, 2 vol. t 1. 16 s. 7. Newtoni Philofophiae Naturalis Principia Mathematica. Edit, opt. 8. Idem Liber, Charta Magna, 18 s. 9. Sir Iiaac Newton’s Treatife on the Quadrature of Curves, and Analyrts by Equations, tranflated, with a Commentary accommodated to the Capacity of Beginners. By Profelfor Stewart. 1 z s. 10. Sir Ifaac Newton’s Obfervations on Daniel and the Apocalypie. 4s. ir. A Treatife of Navigation; containing the Theory and Practice of that Art, with 12 Copper-plates. By Jofeph Harris, Efq; his Majefty’s Aflay Mafter of the Mint. 6 s. 1 2. Dr. Halley’s Tabula Afironomica, with the Precepts, both in Latin and Englijb. 1 8 s. 13. Cmfaris Commentaria, cum variorum Notis ; recenfuitDavifius. 8s. 14. Robertfoni Thefaurus Lingua; San&te, five Concordantiale Lexi- con Hebra;o Latino Biblicum. 12 s. 15. Albin’s Natural Hiftory of Birds and Infedls, finely engra-ved and coloured, 4 vol. 16. Memoirs of Milton, with fome curious Hiftorical Pieces. By Mr. Peck. 6 s. 17. Milton’s Memoirs of Oliver Cromwell, with curious Hirtorical Pieces. By Mr. Peck. 6 s. 18. Capt. Dobbs’s Account of the Countries adjoining to Hudfon’s Bay ; their Situation, Climate, Trade, Navigation, &c. with an Ab- iiradt of all the Difcoveries that have been pubiiihed of the Wands, &c. in the Great Weftern Ocean ; Vocabularies of Indian Languages, &c. 5 s. 19. Elilob’s Rudiments of Grammar for the Sakon Tongue. With an Apology tor the Study of Northern Antiquities. Very ufeful towards the underiianding our ancient Engliih Poets, and other Writers. Being the only Saxon Grammar in the Engliih Language. 2 s. fid. 20. Foflili^ Hantonienrta : Forth Shells, colledled in the County of Ilamplhire; the greatert part of which, upon a compar.fon with the re- cent, arc wholly unknown to us. They arc exquifitely engraved from the Branderian Collodion in the Britilh Mufenm, with a Laiin Defcription by Dr. Solandcr, and a prefatory Account in Latin and Engliih. ios. 6 d. 21. A Natural Hi rtory ofFortils, upon a new Syllein ; in which they arc arranged lo as to be more accurately diftioguilhed than by any other hitheito followed. To the Dderiptions arc added hirtorical Faffs, and critical Obfervations. By Mr. Da Coitu. Voi. I. Containing, Series I, Earths. Series II, Stones. 12$.